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[[quoteright:300:[[Creator/MCEscher http://static.tvtropes.org/pmwiki/pub/images/another_world2_9367.jpg]]]]
[[caption-width-right:300:[- [[Literature/OfMiceAndMen Which way do I go]], [[Creator/HPLovecraft Jh'rj]], [[WesternAnimation/LooneyTunes which way do I go?]]-] ]]

->''"...but you start with parallel lines that ''intersect'' and you go from there."''
-->-- '''Black Mage''', ''Webcomic/EightBitTheater'', [[http://www.nuklearpower.com/2008/06/12/episode-1004-fun-house/ #1004]]

A staple of CosmicHorrorStory and of MindScrew artworks. [[EldritchAbomination Elder Gods, Old Ones,]] the RealityWarper, TheOmnipotent and other [[CosmicEntity cosmic entities]] tend to bend the laws of physics to suit them. Why make a triangle where the angles add up to 180 degrees, when you can make one where they add up to 200 degrees in a flat space and get some extra room? Even the very ''body'' of a particularly squamous thing may exhibit this, though more often it shows up in architecture as physically-impossible buildings—[[GeniusLoci occasionally sentient themselves]].

Alien Geometries are often depicted as being [[GoMadFromTheRevelation dangerous to the sanity of normal humans]]; where you have to ''read'' the TomeOfEldritchLore for it to drive you crazy, just ''looking'' at this stuff can have an [[BrownNote unpleasant effect]] on your mental stability. Or at least really give you a headache.

More innocuous forms may appear normal. Then you realize that it is physically impossible for [[BiggerOnTheInside something this size to fit in that]], or you travel a short distance and find yourself kilometers away, or you turn left and end up to your right. Doubly fun if found in the MobileMaze.

{{Eldritch Location}}s are a good place to find this. Sometimes it is a single wall or building that is just a little... ''off''. See also HyperSpaceIsAScaryPlace, an entire alternate universe that just does not make sense. A MinusWorld in video games might be considered one due to [[GoodBadBugs unintentional programming bugs.]]

Compare with {{Bizarrchitecture}}, SinisterGeometry, and ScoobyDoobyDoors (when done for comedy).

----
!!Examples:

[[foldercontrol]]

[[folder:Anime and Manga]]
* ''Anime/NeoHumanCasshern'' shows what appears to be a metal bolt of lightning -- or a metal construct -- striking from the sky and staying in place for several days, inciting a transfer of what we are led to believe is superdimensional energy into our dimension. This energy is visible in the form of sparkling mystical runes hovering in the air facing the observer. ''It's awesome''.
* The [[AnotherDimension Reverse World]] in ''Anime/PokemonGiratinaAndTheSkyWarrior'' is an [[Creator/MCEscher Escher]]-like place where "up" varies, but [[FridgeLogic apparently only for landbound creatures]] (see the ''Pokémon Platinum'' note in Video Games below).
* ''{{Mononoke}}'', in the Zashiki-Wareshi arc, the cast is trapped in infinite, identical copies of the same room.
* The Angel Ramiel in ''Anime/RebuildOfEvangelion'' manages to pull this off with some aplomb; its internal facets constantly shift as it moves, and the very first time we see it shift shapes from its fairly mundane octahedron to... other things, we see that it is somehow ''impossibly deep'' and one piece all at the same time... and then it starts changing shape when firing beams of pure killing. The effect is enhanced by the fact that what it does is almost ''painfully'' easy to render in CGI, but to see a physical object actually ''do'' it would be skull-crackingly horrifying.
** Leliel in the original ''Anime/NeonGenesisEvangelion'' appears out of nowhere over the city as a giant, floating sphere with black and white stripped patterns on it. But when the Evas fire at the Angel, the sphere fades out to dodge the shots, then casts a shadow which absorbs everything into it. It's then discovered that the sphere isn't its body: the angel is a 600-meter wide and 3 nanometer thick disc that is connected to a [[http://en.wikipedia.org/wiki/Dirac_sea Dirac Sea]]. The floating object is actually a 3D shadow that appears when the Sea is opened. It gets even more mind numbing when you realize that the "shadow" is NOT intangible: it [[MindScrew casts its own shadow]] and can physically interact with other objects ([[{{Gorn}} Unit 01 tearing its way out]], in particular). It can even ''bleed''.
** Pretty much every Angel in both the television and Rebuild universes seems to exercise this trope. Special points go to the Rebuild version of Zeruel, for being apparently solid and hollow at the same time, and being full of blood while also able to unravel itself into razor-sharp ribbons.
* Witches in ''Anime/PuellaMagiMadokaMagica'' live in sprawling horror-filled labyrinths. Their alien nature is highlighted by Russian- and Czech-inspired animation, whose flat cut-out geometry is in stark contrast to the cutesy Japanese animation in the rest of the show.
* The third season of ''Anime/SailorMoon'' does this when one of that season's miniboss squad accidentally breaks reality, resulting in the entire house becoming a zone of warped space.
* The Maze card in ''CardCaptorSakura'' creates a [[TheMaze maze]] that isn't bound by normal spatial physics.
[[/folder]]

[[folder:Comic Books]]
* In the {{JLA}} storyline ''Rock of Ages'' the Joker nearly drives Superman and the Martian Manhunter mad by trapping them in a maze-like satellite, the structure of which is controlled by his subconscious mind.
* In his Silver-Age ''Comicbook/{{Superman}}'' wrap-up, ''ComicBook/WhateverHappenedToTheManOfTomorrow'', Creator/AlanMoore reveals Mr. Mxyzptlk's "true" form, described by Lois Lane as consisting of "height, length, breadth, and a couple of ''other'' things... looking at it made my head hurt." Moore likes having characters encounter and be upset by non-Euclidean phenomena; later in the same comic the room containing the Phantom Zone portal is described as eerie and unpleasant.
* Creator/AlanMoore does this again in ''ComicBook/TomStrong's Terrific Tales'' where Strong and Svetlana X find a Russian space station has become crystal-filled and BiggerOnTheInside with multiple centers of gravity. [[spoiler:The whole thing was caused by a chance encounter with a higher-dimensional cosmic particle.]]
* The crashed alien spaceship in ''Comicbook/{{Miracleman}}'' is probably one of the most distinct of Moore's uses of the trope, and is thus very difficult to describe. The people who board the ship all suffer from headaches and dizziness from the sheer disorientation that navigation of the craft causes.
* In one strip of ''ComicStrip/CalvinAndHobbes'', the law of perspective is repealed, meaning that the sizes of objects no longer depend on how far away they are, making it impossible to tell where anything is. This is all happening in Calvin's imagination, of course.
** In another sequence, when Calvin was told to look at things from multiple perspectives he took literally and started seeing things as a Cubist painting, and another time when he used supposed lack of depth perception as an excuse for running into furniture.
* This is generally how much of {{Galactus}}'s technology is portrayed in Marvel comics. An alternate universe version of Reed Richards once spent decades figuring out the technology of a single room in the alien creature's massive home.
** Galactus's aforementioned house, the Worldship Taa II, also qualifies; it's a gigantic spaceship that dwarfs nearby planets without altering their gravitational fields.
* ''ComicBook/AlphaFlight'' - Shaman's medicine pouch has its own laws of physics, able to hold far more than its volume, as well as responding to its owner's wishes as to what he wants. Anyone inexperienced in Shaman's magic style who looks into the pouch risks going catatonic.
** '''Don't turn it inside out.'''
* ''Comicbook/SwampThing'' - The Demon {{Etrigan}} employed Alien Geometries in an incantation to create a path from Hell back to Earth during Creator/AlanMoore's run, when Swamp Thing rescued his beloved Abigail from Hell:
-->"Thou quantum imps and cherubs by whose dance\\
Is substance formed to shape the fields we know\\
Your perfect waltz that conjures form from chance\\
Must pause to free us from these wastes below.\\
By root of minus nine and circle squared\\
Set right and true against dimensions three\\
Let our ill-angled passage be prepared\\
Between the folds of rare geometry."
* During the Troll War sequence in ''ElfQuest'' Wendy Pini drew one panel with deliberately Escheresque geometry, showing a spiral staircase from the side with the characters at the top appearing much bigger than those at the bottom.
* A scene from FirstComics' ''{{Elric}}: The Sailor on the Seas of Fate'' depicts Elric in the captain's cabin, leaning down to look at a model ship. The viewpoint zooms in through the model ship's porthole, revealing Elric and the captain inside.
* DonaldTrump's hair, as portrayed in ''{{Doonesbury}}''.
* The Bojeffries' house in ''ComicBook/TheBojeffriesSaga'' has a trapdoor that ought to lead to the loft but which opens in the back garden.
[[/folder]]

[[folder:Fanfiction]]
* ''FanFic/HarryPotterAndTheMethodsOfRationality'', in line with the original ''Literature/HarryPotter'' series, has this: Hogwarts' corridors which can change when you aren't looking. The number of stairs you climb has only a passing correlation to your actual elevation when you look out the window. At least one corridor is tiled in pentagons.
** A newer chapter describes a stairway in Ravenclaw Tower as being straight when viewed from the inside and actually climbing it, but viewed from the outside, logically only a spiral staircase could fit.
* ''Fanfic/ABoyAGirlAndADogTheLeithianScript'': This ''Literature/TheSilmarillion'' fanfic provides two examples:
** [[ElaborateUndergroundBase Ang]][[GrimUpNorth band]] -the equivalent to Hell in this story- was erected and designed by [[BigBad Mor]][[GodOfEvil goth]], and it is built in very weird shapes that make no sense to men or elves. People who has been inside barely can describe the place (beyond vague words such like “ugly”, ”burnt”, ”angled” “deep”, “rough” and “paths and overpasses winding up and down and you never know what direction you are going towards”) or they do NOT want to remember what it is like. The ex-thrall confirms that nothing of its design suggests that it was built by elves, and Luthien said that none of the architecture seemed designed with people in mind at all, but it was actually designed to NOT seem homely.
** The [[TheLifestream Halls of Mandos]] are a minor example. They are an underground network of halls, tunnels and corridors dug under the Aman’s Western ranges. The stonework and architectural style is plainly different of anything built by men, walls and rooms can be rearranged with enough will force and distance and direction work in strange ways, but at last you can understand the designs.
* ''FanFic/ADifferentMedius'' has The Dead Sea, which resembles a cross between an M.C. Escher painting, and Cthulhu's domain.
* In ''FanFic/FuckTheJesusBeam'', there is a city that literally ''does not exist'', as it is only a lie. Despite this, it is also a physical location. Given the name Αδιβ, when someone who can see in only three dimensions looks at it, it appears normal, but in progressively higher dimensions, the architecture becomes more and more bizarre.
* In the Pokémon fanfic ''FanFic/AshsReturn'', the doors in Glitch City manifest this way to anyone trapped inside.
* The ''FanFic/PonyPOVSeries'' has [[BigBad Discord]]'s castle in the [[BadFuture Dark World]]. It constantly shifts both interior and exterior -- seemingly as much of its own will as Discord's -- and for bonus points, even contains a void that's a portal to his cousin [[EldritchAbomination Ponythulhu]]'s domain.
* In ''FanFic/FalloutEquestriaProjectHorizons'' at one point there is an attack spell that appears to be this. It appears as some sort of distortion, and shatters bone without damaging flesh. Light would be distorted if the space it moved through was. Flesh is stretchy and can survive the fact that the angles on a triangle no longer add up to 180 degrees. Bone, not so much.
* In the climax of ''FanFic/SonicXDarkChaos'', the [[GeniusLoci Dark Chaos Planet]] is made up of both this and hefty doses of MindScrew. Tails lands on the constantly-shifting surface and jumps into a pit that leads into the core; he lands and enters the core after a few seconds of falling sideways.
* ''FanFic/{{Scootamom}}'': Princess Celestia's first attempt at knitting goes very wrong, and the resulting... ''[[HomeMadeSweaterFromHell something]]'' manages to warp time and space around itself. It makes ordinary ponies ill just looking at it.
[[/folder]]

[[folder:Films -- Live-Action]]
* The Overlook Hotel in ''Film/TheShining'' has hallways that lead into walls, windows that can only be seen from inside, hotel rooms that seem to overlap the same space, and doors located too close together to lead to separate rooms.
* An indie black-and-white short film of ''The Call of Cthulhu'' by [[http://www.cthulhulives.org/toc.html The H.P. Lovecraft Historical Society]] does a particularly good job of getting this idea across, in a scene (faithfully adapted from Creator/HPLovecraft's story) wherein a victim falls into a crevice which an optical illusion has led the audience to believe is a convex crag of rock.
* ''Film/Cube2Hypercube'' is a rare example of this trope being employed in a visual medium. The actual warped geometry shows up only a few times due to the special effects required being rather expensive; the rest of the time it's showcased indirectly (e.g. duplicates of characters showing up).
* The climactic scene of ''Film/{{Labyrinth}}'' takes place in an [[Creator/MCEscher Escher]]-esque landscape where 'up' varies. The scenery was based on a drawing by M.C. Escher.
* The [[{{Phlebotinum}} Red Matter]]-generated black holes in the new ''Film/StarTrek'' movie. From the front, they look like your average [[SwirlyEnergyThingy swirling]], [[UnrealisticBlackHole funnel-shaped]] NegativeSpaceWedgie. Approach from the side, and you can see that it's ''missing its third dimension.''
* ''Film/GraveEncounters'' plays with this quite a bit a short distance into the movie. [[spoiler: the doors that should lead outside now lead to more hallways, corridors are either entirely blocked off or in wrong locations, and time seems to pass at its own rate inside the demonic hospital which makes it impossible to tell what time it is without a watch or cellphone.]]
* The tesseract-thingies during the "beyond the infinite" sequence from ''Film/TwoThousandOneASpaceOdyssey''. Just look at them, and the way they move.
** Even more impressive when you consider that they were created in the pre-digital era using 28 precisely-timed exposures.
* The Tanz Akademie from ''Film/{{Suspiria}}'', an art deco nightmare from hell.
* Dream levels in ''Film/{{Inception}}'' are built like this deliberately by the level's "architects," in order to trap and delay the subconscious projections of the dreamers to keep them from attacking. The strange architecture can even be weaponized, as demonstrated by Arthur at one point, where he flees from a projection shooting down at him from the top of a staircase...only to have Arthur alter the stairs into a Penrose Staircase (looping stairs) and attack the projection from behind.
* ''Film/LastYearAtMarienbad'' was shot within several castles and edited together to create a lack of continuity in the castle and a strange, disorienting effect.
[[/folder]]

[[folder:Gamebooks]]
* If you try to map the Citadel in the ''FightingFantasy'' gamebook ''The Citadel of Chaos'', you'll quickly find its rooms are connected in contradictory ways and sometimes occupy spaces that should be beyond the outer walls. Maybe Jackson just wasn't too strict about the layout, but it ''is'' called the Citadel of ''Chaos''...
[[/folder]]

[[folder:Literature]]
* The Monoliths in ''Film/TwoThousandOneASpaceOdyssey'' have the dimensions 1 by 4 by 9... [[spoiler: "And how naive to have imagined that the series ended at this point, in only three dimensions!"]]
* The House of the Maker from ''TheFirstLaw'' trilogy by Joe Abercrombie. The protagonists enter about halfway up, walk around a bit inside but never ascend or descend, then exit on the roof. Most of the characters can't wait to get out of the place, even if it does involve crossing the narrow, rail-less, hundred-foot-high bridge. And there's always the possibility of leaving the place ''before'' entering it.
* This happens a lot in ''TabletopGame/{{Warhammer 40000}}'' when the Powers of Chaos are involved.
** In Creator/GrahamMcNeill's ''Warhammer 40000'' ''Literature/{{Ultramarines}}'' novel ''Dead Sky Black Sun'', the city in the [[{{Mordor}} Eye of Chaos]] features this — producing a MobileMaze with it.
** In Creator/DanAbnett's ''Literature/{{Eisenhorn}}'' novel ''Xenos'', the saruthi "tetrascapes" include regular octagons that nevertheless tessalate. Eisenhorn rescues some [[NewMeat green soldiers]] from such a tetrascape, and later chooses them over experienced soldiers to go into one. Wise of him: the green soldiers had actually seen a tetrascape before, and the experienced ones hadn't. As a result, the "greens" manage to shoot and kill dozens of enemies, but the elite Deathwatch Space Marine attached to Eisenhower's squad can't hit ''anything'' thanks to the effect the twisted geometries have on ballistics.
** In Creator/DanAbnett's Literature/GauntsGhosts novel ''His Last Command'', a [[CoolGate Chaos warp gate]] throws Maggs and Mkoll into a place where [[AlienSky stones hang in the sky and the stars are all wrong (both)]], as well as being [[EvilIsDeathlyCold bitterly cold]]. Also, their vox units register as both within ten kilometers and out of range.
** In Creator/BenCounter's ''HorusHeresy'' novel ''Galaxy In Flames'', Death's Tomb is bigger on the inside than the outside — as well as other repulsive features.
* ''Literature/AliceInWonderland'' - Alice, in Creator/LewisCarroll's ''Through the Looking Glass'' set to walk to a hill and always found herself walking into the doorway of the house. Finally, when she walked away from it, she reached it.
** Lampshaded by the Red Queen, when Alice found herself unable to run quickly. "Now, here, you see, it takes all the running you can do, to keep in the same place. If you want to get somewhere else, you must run at least twice as fast as that!" The Queen was able to travel much faster, since she was a Queen, [[ChessMotif and can cross the width and breadth of the chessboard in a single move.]]
* ''Literature/HouseOfLeaves'' starts with a [[color:blue:house]] that is 3/8ths inch BiggerOnTheInside than on the outside. They are only able to measure all the way across because [[spoiler:a closet mysteriously appeared in the house when they left for a week]]. They also get slightly different measurements with every method they try until confirming the final number with a very accurate method -- you'd ''normally'' think this is because of measurement deficiencies, but in retrospect... Also, this discrepancy disappearing is, believe it or not, the cue for things to get worse.
* ''Literature/ThursdayNext'''s Uncle Mycroft, among his other MadScience projects, developed "Nextian Geometry" with his wife, said to be based on how a cylinder looks like a rectangle from the side, which allows one to use a circular cutter on dough without any left over: it makes circles tesselate.
* Creator/RobertAHeinlein:
** The short story ''Literature/AndHeBuiltACrookedHouse'' involves an architect who, inspired by higher-dimensional geometry and high real-estate prices, builds a house in the shape of an unfolded hypercube. Then an earthquake makes it fold in on itself into a hypercube, so to the architect's delight it's eight times roomier on the inside than on the outside. Just one small problem: the house's new topology makes it a bit difficult to leave once you're inside. When you do get outside, you may have a whole new problem.\\
\\
A math-nerd resident of ''SecondLife'' actually went and reproduced the Crooked House in 3d, and if it's still rezed somewhere public you can actually walk through it. Not a real hypercube of course but some excellent special effects. [[http://nwn.blogs.com/nwn/2006/06/_and_he_rezzed_.html Here's the story with video.]]
** ''Literature/GloryRoad'' had the hero and companions invading a tower "where the architect used a pretzel for a straight-edge." It's so convoluted that it took hundreds of spies decades to figure out a route to the MacGuffin.
** ''Literature/TheNumberOfTheBeast'', as well: we're only seeing dimensions x, y, z; but there are at least three others which can be rotated around or extended along, and which apparently can be used to travel between universes. This is a conceit to let him run through every literary universe ever, and have a massive CrossOver event. The novel culminates in a party, in what is effectively the Crooked House, with every single character he created attending (plus several guests). Special mention goes to the [[AcceptableTargets literary]] [[TakeThat critics]] lounge, which was shaped like a Klein bottle... once you were inside.
* ''Literature/DeepSecret'' - the [[PlaceOfPower Hotel Babylon]] has halls where you can go around more than four right angles before coming back where you started thanks to the building being on top of a bunch of {{ley line}}s.
* ''Literature/TheWheelOfTime'' - The Aelfinn and Eelfinn ("the Finn") inhabit one or more separate dimensions described by the author as having radically different natural laws. Successive windows do not show what one might expect. That the magic system in the series is heavily geometric likely has a great deal to do with why its use is explicitly forbidden there. The doorways into their realm also resemble this in the "real world", and are described as "twisted".\\
\\
Though it's less apparent, the same is true of the Ways, an artificially-constructed dimension meant for quick travel. Except in one dream sequence (which, for complicated reasons, probably reflects the reality of the Ways), the realm is extremely dark, but travelers there have noted that by the arc of the bridges they're walking on, the platform they've just arrived at should be directly beneath the last. During the dream sequence, it becomes apparent that the platform-islands extend infinitely downward—and unless you follow the bridges with your eyes, appear to be on the same plane. The doorways seem to be a description of a three-dimensional Möbius strip.
* A rare ''Franchise/StarWars'' example can be found in Franchise/StarWarsExpandedUniverse novel ''Lando Calrissian and the Mindharp of Sharu''. In it the titular character finds the titular artifact - which seems to exist in several dimensions simultaneously and as such it really hurts just to look at it. Lando then uses it to unlock the passage into the Great Pyramid of Sharu - where he is expanded in size several dozen times, while his droid companion is shrunk to the size of a louse. There are even more examples of AlienGeometries in the book: the aliens who built it were [[StarfishAlien very, very alien indeed]] by ''Franchise/StarWars'' standards.
* Creator/StephenKing:
** ''Literature/NightShift'' - Inverted in the short story "I Am the Doorway". An alien lifeform [[HumansThroughAlienEyes sees]] a boy walking with a sieve under his arm: "an abominated creature that moved and respired and carried a device of wood and wire under its arm, a device constructed of geometrically impossible right angles."
** In Stephen King's short story ''Literature/FourteenOhEight'', the titular room's door is crooked to both the left and the right. Or not at all. Maybe it can move? And it gets worse from there.
** In Stephen King's novel ''Literature/FromABuick8,'' the titular car is actually an interdimensional portal/device that only looks like a car. It's noted that the human eye perceives it as a car because that's the only image the mind can supply for the actual shape of the device.
* A significant plot device in MadeleineLEngle's ''AWrinkleInTime'' deals with folding space-time through a fourth space-dimension for teleportation.
* Creator/CSLewis used something similar in ''Literature/ThatHideousStrength''. One character is briefly imprisoned in the "Objectivity Room", where everything is slightly off—the spots on the table are arranged ''just'' short of obeying a pattern (even a broken one), the similar specks on the ceiling are ''almost'' the mirror-image of the table, and the peak of the arched entryway looks like it might be just a ''fraction'' off-center to the left. Or not. Maybe the right? And let's not start on the paintings...
** JustifiedTrope: The room was specifically built this way to drive people crazy so they'd be suitable hosts for the demonic powers.
** He also appeared to use this in ''Literature/OutOfTheSilentPlanet'', but the room turns out be normal human geometry, just a very unusual sort.
* Creator/HPLovecraft loved non-Euclidean geometry:
** The sunken city of R'lyeh. In ''Literature/TheCallOfCthulhu'', a unfortunate human visitor to this locale is swallowed up by an angle of masonry which is acute, but behaves as if it were obtuse.
*** Before that there is the famous scene where the gate that seals the Great Old One himself opens, and the sailors can't even be sure whether it's a vertical door or a horizontal hatch - even though one of them climbed or walked up its surface!
** The Antarctic city in ''At The Mountains Of Madness''.
** Perhaps most explicit in ''The Dreams in the Witch House'' where a mathematics student discovers the unearthly topology of his own bedroom serves as an extra-dimensional portal. Well, he ''was'' renting it because of its reputation as being haunted. This was a bad idea.

* ''The Hounds of Tindalos'', by Lovecraft's friend Frank Belknap Long, features ravenous creatures of weird geometry who travel trough time and space, and the only way to avoid them once they're on your trail is to completely avoid sharp angles (such as in a completely circular room).
* ''Literature/{{Eon}}'', by Greg Bear, features an asteroid hollowed out by people from ..elsewhere, with seven chambers running along its internal axis. The first six contain cities, parks, a spaceport and loading area, and power generators. The seventh chamber [[spoiler:goes on forever, contains objects made from redistributing probability over space, and a mathematical singularity running along its centre.]] And ''then'' things start to get weird.
* ''Literature/{{Discworld}}''
** Bloody Stupid Johnson, architect, BunglingInventor, and general anti-genius regularly does this kind of stuff ''entirely by accident''.\\
\\
He once designed a letter-sorting machine whose central component was a wheel that had π equal to ''exactly'' three (he did this because he thought that π = 3 point whatever was "a bit untidy"). This causes it to sort out letters it hasn't had put in yet, among other oddities.\\
\\
Empirical Crescent, a row of terraced houses where every door and window leads somewhere other than where you'd expect it to lead. At least it makes it easier to get rid of rubbish—just toss it into the garden. After all, it might not be your garden.\\
\\
The reason for this corruption of dimensions occurs because the row of houses is crescent-shaped on the outside only. Inside, it's supposedly laid out like a straight row. Presumably the two configurations conflict. Occupants had a tendency to leave in the middle of the night, often without stopping to pack...\\
\\
It's also stated in ''Discworld/{{Thud}}'' that he invented the 13-inch foot and a triangle with three right angles.
*** Circles with π = 3 and triangles with three right angles both do in fact appear in non-Eulidean spherical geometry.
** ''Discworld/TheColourOfMagic'' featured a parody of Alien Geometries: the Temple of Bel-Shamharoth (itself a spoof on CosmicHorrorStories). The most striking feature of the Temple is that its walls, ceilings and floors are composed entirely of interlocking regular 8-sided tiles. Whilst it is possible to create octagonal tiles that can be fitted in a regular, interlocking way, they must be concave polygons: there is a mathematical proof that no convex polygon of seven or more faces can tessellate on a Euclidean plane.
*** The first chapter mentions one of the gods using a 7-sided (but still cube-shaped) die to cheat.
** The buildings of the Unseen University, which have been rather strongly influenced by the vast amount of magic that has flowed through its halls over the centuries, have floors and rooms where logic says they simply could not exist. Magic is as much a part of the architecture as cement.\\
\\
It is specifically noted that there are rooms in which gravity changes direction through the day and windows that only exist on one side of their walls.
** The Library of the Unseen University is a particularly strong example—the presence of so many ancient magical texts distorts space-time like an elephant on a trampoline, dimensions and gravity being twisted into the kind of topographical spaghetti that would cause even Creator/MCEscher to go for a good lie down (or sideways). That's quite apart from the fact that it serves as a gateway into L-Space, and is therefore linked to all libraries everywhere in all points of space, time and reality. Technically, it contains every book that has ever been written, every book that is ever going to be written, and every book that ever ''could'' have been written (whether it actually was written or not).\\
\\
Once, the Librarian took a trip deep into the shelves, passed tribes of lost students, and ended up in the same library in the past.\\
\\
In addition, Pratchett explains that any sufficiently large collection of books (magical or otherwise) can exert the same effect as the Unseen University Library; the equation goes "Knowledge = Power = Energy = Matter = Mass". And since mass warps space around it, so does a high quantity of knowledge.
** Death's house is bigger on the inside than on the outside, being the size of a cottage on the outside, but the size of a small castle on the inside. This is not so much intentional, but is rather the result of a slight blindness to ordinary architecture on Death's part. Many of the rooms have the peculiar effect of being enormous at the same time as being regularly sized. Death's room in particular is stated to be about a mile wide, but most can be crossed in only a few steps.
*** The real killer is that Death himself is weirded out by this last fact. This is because it's ordinary humans (like Albert) who cross the room in a few steps, even though it's clearly a mile wide. Death's theory is that the human mind refuses to accept the true size of the room, and acts as if it were normal sized.
** The Tooth Fairy's house in ''Hogfather'' is another example of this trope.
*** The exterior portion of the Tooth Fairy's domain are also a rather interesting take on this trope as the Alien Geometries present are actually based off the poor understanding of size, proportion and three dimensional imagery present in a child's drawing. The massive white gap where there ought to be a horizon is particular unsettling.
** The Gnarly Ground in Lancre is a seriously bizarre landscape of crags and valleys "scrunched up" into a small area, overlapping in space; what geographical features you see there and have to deal with depend largely on your mindset. It makes a good hiding place.\\
\\
It is also known that how you perceive features of the Gnarly Ground depends a great deal on your own outlook. What one person sees as a shallow stream at the bottom of a ditch bridged by a large slab of rock can appear to others as a roaring torrent pounding over boulders at the bottom of a deep gorge bridged by a narrow, shaky bridge of balanced rocks. The most disturbing aspect of this is that how one perceives the features controls how one interacts with them, so one person may see you hanging by your fingertips while another sees you standing in the stream.
** Unseen University's mad but GoodWithNumbers Bursar has posited that there is an extra number between three and four, which he calls 'umpt' (as in, 'umpteen' minus ten).
** The Bugarup University (the UU's counterpart in [[LandDownUnder Fourecks]]) has a tower which is only thirty feet tall at the bottom, but half a mile tall at the top, making it both significantly taller and significantly shorter than the Unseen University's famous (and surprisingly Euclidean) 800-foot tall Tower of Art, depending on where you're standing.
* In JohnCWright's ''Literature/ChroniclesOfChaos'', Vanity's secret passages often don't add up, geometrically, with the places they go to and lead from.
* In ''Time's Eye'', by Creator/ArthurCClarke, there are spherical alien objects that apparently have a 1-to-3 ratio for their diameters and circumferences, instead of a one-to-pi ratio.
* The Starfish structures in ''Literature/BlindLake'' have disturbing interior geometry. Robot probes (and people) who go in too far don't come back. The deep interior seems to be entirely exempt from the usual rules of time and space.
* In the eighth book of the ''{{Everworld}}'' series, the main characters are cast into an inverted realm where the ground they stand on is ''above'' their heads, and gravity pulls them ''up'', with the colors of everything reversed for good measure. This naturally strongly bothers David, April, Jalil, and Christopher. [[HotWitch Senna]], however, ''likes'' it, and compares the reversed plane to fine art.
* In StephenBaxter's short story collection ''Vacuum Diagrams'', the story [[http://kasmana.people.cofc.edu/MATHFICT/mfview.php?callnumber=mf906 The Eighth Room]] deals with something similar to Heinlein's story. However, in this case, the room was not created accidentally... it's more of a logic puzzle. I'll leave it there.
** There's also another short story by Baxter called "[[http://kasmana.people.cofc.edu/MATHFICT/mfview.php?callnumber=mf907 Shell]]", set on a planet that is ''folded in on itself''. There is no sky — people looking up see [[HollowWorld the other side of the planet curving over them, as if it's a shell]]. When one character uses a hot-air balloon to explore the other side, she witnesses the "shell" flatten out and then become curved normally, while the land she just left curves into a shell over the sky.
* In Creator/AmbroseBierce's "The Damned Thing", a creature, judged by ignorant folk to be a mountain lion (from its leavings, since the creature itself is never seen), is a color that the human eye cannot see and makes noises that the human ear cannot hear. This inverts this already inverted trope because the color is natural and it is humanity that has become too alien (or at least insensitive) to comprehend it.
* In the ''Literature/{{Deathstalker}}'' series the [=AIs=] of Shub constructed a world of their own to live on. Unfortunately for humans who might visit, it exists in more dimensions than they can perceive and so is unhealthy to look at for extended periods of time. The Madness Maze, despite a relatively innocuous appearance, had convoluted, nigh-sentient path designs that would either evolve you into a higher being or tear you apart.
* In ''Literature/{{Flatland}}'', the two-dimensional protagonist A. Square struggles to fathom the third dimension when he is introduced to it by a travelling sphere, and it [[GoMadFromTheRevelation almost drives him insane]]. In a dream he sees that inhabitants of one-dimensional Lineland are similarly incapable of comprehending the second dimension. And let's not even get into [[IgnorantOfTheirOwnIgnorance Pointland's issues]].
** Many sequels have been written. ''Flatterland'' (Ian Stewart) has even ''more'' bizarre geometry, including a hyperbolic world, a fractal world, a grid world, and so on.
* ''Threshold'' by Caitlin Kieran contains a fossil in a shape that cannot exist, causing the heroine to [[GoMadFromTheRevelation black out when she looks at it too long.]] What is this sinister shape? [[WritersCannotDoMath A regular heptagon.]]
* In the ''Series/StarTrekVoyager'' novel ''The Final Fury'', Captain Janeway, Tuvok, and Neelix arrive aboard a Fury planet wherein the hallways and doors meet at angles that aren't quite "right" -- literally and figuratively -- and the aliens themselves despise those who follow the "right-angle" or "right-hand path."
* A feature of the bizarre planet in ''Literature/TheInvertedWorld''. Within about a dozen miles of the "optimum", everything is pretty much Earth-like. Go any farther than that, however, and things start to distort unpleasantly. Because the optimum is constantly moving, [[BaseOnWheels the entire City has to move after it]] to avoid destruction.
** Even weirder, [[spoiler:in the novel version, it turns out that the Inverted World is actually EARTH - the inhabitants of the City only perceive it the way they do because their perceptions (and possibly their physical reality) have been altered.]]
* The protagonist of ''Literature/ReturnFromTheStars'' comes back to Earth after over a hundred years of absence. In the meanwhile, architecture has changed/evolved so much and [[{{Bizarrchitecture}} so confusingly]] that when he first steps out into a spaceship depot, everything around looks to him like an abstract, shapeless muddle of pathways.
* In the Literature/StarTrekShatnerverse novel ''The Return'', The Borg have built a hypercube base inside a subspace tunnel.
* ''TheLastBattle'', the final volume of ''TheChroniclesOfNarnia'', ends in a world that's essentially the opposite of reality, in that the closer you get to the center, the more there is.
* In ''AnElegyForTheStillLiving'', the main character spends a few minutes walking down a forest path before realising he is seeing the same scenery looping over and over again. Also, this passage:
-->''After the man had fallen through every place and every time that ever he had even imagined, he began to fall through the places that his mind could not conceive. He passed into structures that did not follow geometry, saw shapes that had no edges or sides, that extended into themselves and into all directions. He saw triangles with one hundred eighty one degrees. He saw minds that had no reason or morality. He saw colors indescribable to others. He saw the true shapes of his dreams, and the ten dimensions of the earth and sky. He saw what no one saw, felt what no one felt. He heard sounds with his finger tips, and tasted with his ears. He had secrets whispered to him in a language that can't be translated.''
* In GeorgeRRMartin's ''[[Literature/ASongOfIceAndFire A Clash of Kings]],'' Danaerys enters the House of the Undying Ones in Qarth. Once in the antechamber, she makes four consecutive right-hand turns without returning to her starting point.
* In Creator/LarryNiven's ''[[Literature/KnownSpace Protector]]'' the Brennan Monster amuses himself by creating full scale replicas of some of Escher's art, using things like artificial gravity to make them work.
* ''Literature/TheHitchhikersGuideToTheGalaxy'':
** The interior of Slartibartfast's Bistromathics ship in ''Literature/LifeTheUniverseAndEverything''.
** The new and improved Guide in ''Literature/MostlyHarmless'' shifts through a few inexplicable forms.
* In the ''Literature/VenusPrime'' series, the interior of the Amalthean world-ship is described as being made up of nested spiral shells. The diagrams at the back of the last book don't help to make it any easier to comprehend.
* The intricate geometric designs that Cryptics use instead of heads in ''Literature/TheStormlightArchive'' invoke this trope. [[spoiler: And in ''Literature/WordsOfRadiance, a Cryptic named Pattern manifests in the Physical Realm as a complex geometric pattern, implied to be based in quantum uncertainty.]]
* Creator/GregEgan's ''Literature/{{Orthogonal}}'' trilogy features a(n oxymoronically) straightforward example: Time is fundamentally the same as space, meaning that there are technically four spatial dimensions and [[MindScrew no such thing as time]]. The trope is even discussed in-universe when Yalda hypothesizes "four-space" and Giorgio [[LampshadeHanging points out how batshit insane it sounds]].
-->'''Giorgio:''' So according to your theory, an object could have a trajectory entirely [[TitleDrop orthogonal]] to our own?\\
'''Yalda:''' Yes.\\
'''Giorgio:''' It could move with ''infinite velocity''?\\
'''Yalda:''' Yes, that's how we'd describe it. But that's no stranger than saying that a vertical pole has an 'infinite slope': unlike a mountain road, it gets where it's going vertically without bothering to go anywhere horizontally. An object that gets where it's going without bothering to move across what we call time isn't doing anything pathological; in reality, there's nothing 'infinite' about it.
[[/folder]]

[[folder:Live Action TV]]
* The Franchise/DoctorWhoExpandedUniverse speculates that this is the default setting for the interior of a TARDIS in ''Series/DoctorWho'', and that the Doctor's TARDIS projects a more easily comprehended interior so as not to [[BrownNote freak out]] the Doctor's human companions. [[GeniusLoci She is just a sweet old thing.]]\\
\\
In "The Lodger" the Doctor uncovers an alien time-distortion device similar to the TARDIS in the upstairs flat of a British apartment building. Amy, poring over the building plans for the address, discovered that the building didn't even have an upstairs, it was a one-story building. Perception filters kept people from noticing anything out of the ordinary.
* ''Series/StargateSG1'': The spacecraft used by the Goa'uld are relatively normal... until you notice the pyramid on top. Naturally, the entire spaceships can fold up so that their central pyramid can land on a planet-bound pyramid.
** Not to mention how a triangular-pyramid shaped spacecraft can land on a square-pyramid.
* The plot of the (admirably silly) ''Series/StarTrekVoyager'' episode "Twisted," where the ship becomes a maze where no door or hallway leads the same place twice due to a NegativeSpaceWedgie.
* ''Literature/{{Neverwhere}}'' does a very nice demonstration of this in passing. The protagonist is led down into the London Underground, then through a door, and down a stair case. This continues, always going down, until they reach a small door and step out on to the roof of a building.
* ''Series/{{Threshold}}'' involved an alien invasion. The aliens used devices that apparently contained more that four dimensions, and cannot be fully perceived visually. Just seeing or hearing the signals originating from these 'beacons' can kill or transform the view into an alien agent, with triple DNA helix where earthlife has only contains double. The aliens themselves are usually seen in dreams; crystal forests where spider-like entities are only partially seen.
* In the ''[[Series/TheTwilightZone Twilight Zone]]'' episode, "Little Girl Lost", a little girl falls through a portal in the wall of her bedroom into an alternate dimension, in which space is twisted, distorted and nonsensical to ordinary human perception. Fortunately, the family dog's superior hearing and sense of smell help get the little girl back into our dimension [[spoiler:before the portal closed forever]].
* ''In the Night Garden'' is a [[Creator/TheBBC BBC]] ''kids' show'' (from the people who made ''Series/{{Teletubbies}}'') where the various characters often ride around the eponymous garden in the Ninky-Nonk (a train without tracks) or the Pinky-Ponk (an airship). When they're boarding, these vehicles are comfortably large enough to accomodate all of them, yet when they're actually in motion the Ninky-Nonk is small enough to run up trees and over branches, and the Pinky-Ponk is small enough to get knocked off course by a ''toy ball''.
* In ''Series/{{Warehouse 13}}'', the personal effects of permanent prisoners of the Warehouse are stored in the Escher Vault, which is basically a three-dimensional Creator/MCEscher painting. Authorized personnel use special goggles to follow along with the vault's ever-shifting perspective. Unauthorized personnel are never seen again unless they have SuperSpeed.
* In ''Series/RoseRed'', the titular mansion is like this. Sometimes. It was built to perfectly normal standards, but after a series of incidents it went from "just" haunted to [[EldritchLocation something more]], and may in fact have been ''[[GeniusLoci sentient]]''. Features include staircases leading into ceilings, dead-end hallways that screw with perspective, rooms that weren't there a minute ago (or were there but aren't any more), and other hilarities. About the only guaranteed stable locations are the entryway, the attic and the arboretum, and even then the things ''in'' them often are moved around or fully animate.
[[/folder]]

[[folder:Paintings]]
* Paintings by H. R. Giger, famous for his design of the Xenomorph in ''Film/{{Alien}}'', though his work tends more to towards the horror aspect than the impossible. He also likes to paint landscapes having sex with themselves. Think about that for "scenery porn."
* Creator/MCEscher could be considered to make "lite" versions of AlienGeometries; notwithstanding that, his style is often used to represent them. Some of his works are geometrically accurate representations of the sorts of triangle-mangling spaces described in the intro (hyperbolic planes in the ''Circle Limit'' sketches for example). And yes, his work does have an impact on one's sanity...
** Some of his works are what have been called lampoons, because they work by violating normal conventions of art (like things that are behind other things being blocked from view by the things they are behind). The effect of violating rules of art that are present to mimic reality is to make the image look strange for reasons that are not always obvious.
* The LP sleeves of the first two BlueOysterCult records (''Blue Oyster Cult'' and ''Tyranny and Mutation'') depict strangely alien geometries and stuctures under strange skies on strange otherworlds. While nothing violates perspective rules, they still look eye-wateringly odd.
* William Hogarth's print ''[[http://upload.wikimedia.org/wikipedia/commons/6/67/William_Hogarth_-_Absurd_perspectives.png False Perspective]]'' is meant to be a parody of mistakes made by bad artists, but ends up looking very much like a prototype of Escher's style.
[[/folder]]

[[folder:Religion]]
* In Christian eschatology, the end of the world is accompanied by the sky ''rolling up like a scroll''. If this wasn't MindScrew enough, it also involves everyone on earth witnessing the return of {{Jesus}}. At once. Even though the earth is a sphere.
** Remember that during biblical times many nations still thought the Earth was flat, the sky was assumed to be a bowl-shaped dome, and the stars just points of light fixed to it. [[MakesSenseinContext With that in mind, makes sense.]]
** A bit of interpolation between these two, and with modern theoretical physics, and we have a possible MindScrewdriver: The end of the world splits the fabric of space across all of the 3-dimensional universe, revealing Eternity, from which Jesus emerges and destroys the wicked with the brightness of his coming, which may as well mean that [[YourHeadAsplode their heads a'splode]] from the MindScrew of it all.
[[/folder]]

[[folder:Tabletop RPG]]
* In {{Mortasheen}}, this is where the [[http://www.bogleech.com/mortasheen/xenogog.htm Xenogog]] lives naturally, only coming into ours with a screw up in a time travel experiment.
* The near-universal hallmark of things made in the name of Chaos in ''TabletopGame/{{Warhammer 40000}}''. For example the [[AlwaysChaoticEvil Dark]] [[OurElvesAreBetter Eldar]] capital Commoragh has spatial anomalies, "wandering shadows that tear apart the unwary" and many other dire things. It lies deep within a nest of extra-dimensional tunnels.
** The Webway in general seems to follow alien geometries. In particular, gravity seems to always point towards the tunnel floor/walls. In ''Path of the Outcast'' there is a city built into a large spherical chamber in the Webway where buildings cover the entirity of the chamber walls and a person on the streets would see the city curve up and into the "sky". Commorragh is even worse since the place is filled with portals, meaning that walking down the street might actually involve trevalling the distance of several lightyears.
* ''TabletopGame/DungeonsAndDragons''
** The Classic ''Dungeons & Dragons'' system delved deep into this trope with its boxed set for PC Immortals, redefining game-reality in terms of five spatial dimensions. Mortal creatures exist in three, Immortals in four, and Old Ones in five. ''Which'' three a mortal creature occupies can vary: Nightmare-reality creatures share only one spatial dimension with Normal-reality beings such as humans, and "nippers" from the Astral Plane overlap with dimensions of both Nightmare and Normal reality. As for how all this applies to the geometry of the planes themselves, thinking about it could make YourHeadAsplode.
** The Planes in D&D 3rd edition got like this at times, such as an infinite plane having an edge. Seasoned Planeswalkers tended to give the advice "Try not to think about it."
*** In the ''Queen of the Demonweb Pits'' module, the players ventured into The Abyss to confront Lolth, the demon queen of the spiders. Lolth's domain consisted mainly of long, open passageways hanging in space. Even though these passages pass over and below each other, they never ascend or descend in any way.
*** Less heady are the Githzerai monasteries on Limbo, which take advantage of the fact that "down" is whichever direction you want it to be, giving us some extremely Escher-esque architecture.
** Possible example: In ''TabletopGame/DungeonsAndDragons'' fourth edition, as a bookkeeping shortcut, space in combat is explicitly non-euclidean: you can [[DiagonalSpeedBoost move diagonally at the same rate you can move straight]], and if you have a sphere, the shape is explicitly a cube; and yet straight lines remain straight, and a rectangular room still has only 90 degree angles. The result, when you map it out onto normal space, is frankly bizarre.\\
\\
For those of you asking, "How does a world where spheres are cubes make life easier?": the world in question appears to be made largely out of 5' squares, so having a setup where you don't need to wave around ''TabletopGame/{{Warhammer}}'' templates every time someone casts ''Scorching burst'' speeds things up quite a bit (of course, hexagons would have been a closer approximation). Height is implicitly the same as the other two dimensions at some points, and implicitly non-existent in other parts of the rulebook.
** Another good example from ''TabletopGame/DungeonsAndDragons'' is Sigil, a city that exists on its own plane, connected to others only by portals in the forms of doors. The city resembles the inside of a tire; it's a tube that wraps around on itself, so you can look up and see buildings in the sky, walk straight for hours and end up in the same place, and open any door and end up somewhere else. Gravity seems to work for whatever ground your standing on right now and light is just sort of there. To top it all off, it's floating on the top of an infinitely-tall spire in the middle of a plane that is both infinite and finite. The best part, though, is that, since Sigil exists completely separate from any other plane, there is a chance that it has no outer surface.
* ''[[{{GURPS}} GURPS: Illuminati University]]'' describes a campus which teaches human students and everything else capable of paying the exorbitant university fees how to function as {{Mad Scientist}}s, World-Conquering Dictators, Marketing Specialists, and other strange jobs.\\
\\
The campus is a stereotypical university: the campus has an open area or "Quad" in which students and staff may pause for reflection, study, impromptu lectures and other activities from which [[HilarityEnsues adventures may spring]]. Illuminated University has ''The Pent'', which has five sides for [[RuleOfCool no particular reason]]; students who happen to have a protractor handy will discover that all five of the corners have 90-degree angles. One of the dorms is stated as having rather similar angles.
* ''TabletopGame/MageTheAwakening'' has the [[TheMaze Twisting Maze Zone]], a localised distortion of reality caused by [[EldritchAbomination Abyssal forces]]. While it ''looks'' chaotic, a constantly shifting jumble, this is actually because its directions extend into [[TimeTravelTropes the fourth one]] as well. Unlike many examples, mages can use this to their advantage, using their will to walk through hidden parts of it to teleport around-in fact, they must, as the way to banish it is to walk through the areas of the Zone as they normally are-i.e., sans Twisting Maze-thus ''forcing'' them to apply to Earth laws.\\
\\
Once that is done, the Zone literally {{Logic Bomb}}s itself out of existence, causing anybody nearby to gain a brief glimpse into the space-time continuum. Should someone have the force of will to process it, they have an epiphany about how the world works, resulting in an ExperiencePoint gain. If no one does anything about it though, the Zone grows so bad that it ends up [[RetGone rewriting history]] so that it-and the area it affects-ceases to exist.
* And, as you'd expect, ''TabletopGame/CallOfCthulhu'' and ''TabletopGame/CthulhuTech'' occasionally include this for...[[Creator/HPLovecraft well, we all know why]].
* The Terminal in ''TabletopGame/OverTheEdge''. It's Al Amarja's massive airport, nine-storeys high and built like a maze. Navigating it is so difficult, people need to hire guides. Of course, the best part is when you leave the airport and see that it's built like a step-pyramid. An ''upside-down'' step-pyramid.
* The dimensions of [[TabletopGame/{{Exalted}} Primordial world bodies]] are often based on their moods and personalities. For the more focused and stable ones, the worlds are typically consistent and predictable. For others, you get things like spatial relationships that are constantly rearranged, being able to pass from one side of a layer to another with no obvious transition, and having a sun that is inexplicably always right above you while also being at the center of a spherical arrangement.
** As you might imagine, this makes travel around Malfeas... interesting. Once you enter the dimension proper, you must cross Cecelyne, the Endless Desert, for five days to actually get to the Demon City. No, it doesn't matter if you're walking on foot, riding on horseback, or piloting a First Age airship. The trip ''always'' takes five days. Then you get to the Demon City, which is layers upon layers stacked on top of one another - but each layer has Ligier, the Green Sun, shining above it, no matter how deep down it is.
* ''TabletopGame/WerewolfTheApocalypse'' has the Black Spiral Umbral Realm. Being a SpiritWorld the Umbra is pretty odd at the best of times, but normally follows at least the guidelines of the laws of physics, [[AFormYouAreComfortableWith if only because visitors expect it to.]] But the Black Spiral... From the outside [[ExactlyWhatItSaysOnTheTin it looks like just a spiral pattern on the floor in black.]] Once you start walking it it seems longer, twistier and with entirely too many dimensions. In fact it's a path into the mind of [[EldritchAbomination the Wyrm.]] No-one's ever come out the other side sane.
* In the ''[[TabletopGame/{{TwentyThreeHundredAD}} 2300 AD]]'' module ''Bayern'', explorers who [[spoiler:penetrate the cluster nodes at the heart of the Pleiades]] end up [[spoiler:in the four-dimensional realm of the AGRA Intelligence]]. They may [[spoiler: discover that the Pleiades is just one part of a galaxy-spanning megastructure]], go insane, [[MirrorChemistry end up dimensionally flipped]], or all of the above before they leave.
[[/folder]]

[[folder:Toys]]
* The ''{{Transformers}}'' already skirt the trope, what with size and mass-changing and the oddness of the scales...but then we come to the Autobot Micromaster Countdown's playset. He's a deep space explorer. He has an interstellar rocket and a command base. The base is used to launch the rocket. But also fits inside the rocket: [[YourHeadAsplode mgnaaaaa!]]
[[/folder]]

[[folder:Video Games]]
* ''VideoGame/CryptWorlds'' seems to have shades of this. There is a 'Glitch World' containing flashing shaking spiky walls of random bright colours, fluctuation and moving out of shape all over the place. It's reminiscent of certain computer errors and bugs like Z-Fighting, and missing textures. The whole place seems to exist nowhere.
* In ''VideoGame/TempleRun'', the temple was surely designed by an EldritchAbomination. Or by Creator/MCEscher. Or by a terrain randomizer that doesn't keep track of where you have been, so that it may happily let you take seven quick 90 degree turns to the right in a row and come to a new location each time.
* Unlike binary space partitioning-based 3D engines, portal-based 3D engines organize spaces by where they join together rather than where they are located in space. This means that games like ''VideoGame/{{Marathon}}'' allow multiple entities to occupy the same location without touching under certain conditions, such as a Klein Bottle-shaped level. While the ''Marathon'' series unfortunately doesn't employ it in the actual campaign outside a few Easter eggs, the multiplayer level ''5-D Space'' provides an example of the possibilities.
** Several third-party {{Game Mod}}s do this, for example one level of "Keep the Home Fires Burning" has a 720-degree circular hallway with two overlapping hallways going down the middle. And "Schmackle" in ''Marathon EVIL'' has a part where you go through a portal into an alternate version of the level occupying the same space. Sort of like the "Tier Drops" example below.
** ''VideoGame/DukeNukem3D'' has a similar engine, and its quirks are used to full effect in some of the secret levels.
*** The level "Lunatic Fringe" is a 720-degree circular hallway around a central hub, so you have to walk around the hub twice before actually returning to where you started.
*** The level "Tier Drops" has four overlapping areas connected by a hallway around them and drop tubes inside. The guys at 3D Realms beat the level in just ''ten seconds''.
*** A few of the game's levels actually use these quirks transparently and a number of user-made levels deliberately work to show them off or to fake architecture that's not truly possible with the game engine.
** ''{{Descent}}'' can use similar techniques with user-made levels. One example was appropriately titled "4D".
** A level based on these concepts exists for ''AmericasArmy''. A video of it can be found [[http://www.youtube.com/watch?v=2s4ySkR48cI here]]
** The Source engine as of 2011 has a feature that allows for something like this; they [[MundaneUtility mainly just used it for]] testing unfinished level designs. It can produce some [[http://www.youtube.com/watch?v=_xFbRecjKQA crazy stuff]] if you know how to use it right. Unfortunately, the version of the engine it's in can really only make ''Portal 2'' add-on content for now.
*** Though not used extensively, ''VideoGame/TheStanleyParable'' actually used such features in some of the endings.
** The Unreal engine is also capable of things like torus-shaped levels and endless corridors with creative application of warpzones, right from the earliest version of the engine. It's far from perfect, though: non-projectile or "hitscan" weapons can't shoot through, stacking more than four warpzones results in the engine glitching and drawing the portal surface's texture, warpzones must have the exact same dimensions at both ends or the game will crash, etc.. The level DM-Fractal even has a relatively simple "anyone falling into the floor trap falls out of a hole in the ceiling" trick.
** ''VideoGame/{{Antichamber}}'' abuses this facet of the Unreal engine to create a sprawling, mind-bending, non-euclidean maze, where certain invisible thresholds will cause the place you just came from to be swapped out with something else, but only while you're not looking. The above glitches can [[SpecialEffectsFailure give away the positions of these invisible portals]], though.
*** At one point, you make six 90-degree right turns in quick succession, with all turns being equally spaced out from one another.
*** In one puzzle, you may fall down a pit at terminal velocity for 10 seconds. To return to the room that you originally fell from, you board a not-particularly-fast elevator and ride it up for 1.5 seconds.
*** Frequently, two puzzles that are (presumably) spatially far apart will lead to the exact same destination. If you reach said destination via puzzle 1's path, puzzle 2's path will be nowhere to be seen, and vice versa.
* A little-known [=2.5D=] sci-fi (considering it was made in Russia, nostalgical sci-fi) first person shooter ''{{Madspace}}'' embodies this trope, complete with this feature actually being [[AllThereInTheManual mentioned in the manual]]. If you decided to dig the game out, there's one thing you should consider... never ''ever'' use the ghost cheatcode.
* Games like ''{{Asteroids}}'', 'and the like, use an unwrapped toroidal universe—the environments have the same geometry as the surface of a donut. SuperMarioWar does the same thing by default, but because all the levels are custom-designed, you can modify it to take place in an enclosed space, or add kill zones at the sides of the game window VideoGame/SuperSmashBros-style.
* ''VideoGame/{{VVVVVV}}'' takes place in a WrapAround universe. However, the Tower level is taller than the rest of the universe, but is hard to notice since said level is on auto-scroll.
* ''VideoGame/{{Portal}}'' is based all around this idea. If you shoot a portal into a wall, and then turn around and shoot another connected one into the other wall behind you, you can ''see your own back''. And then, if you wish, run in a straight line forever without ever leaving the space you're in. That's just for starters - try, if you place a portal well, being able to see an ''infinite series of your own back''. It's also fun to place a pair of portals in the ceiling and floor and then fall through endlessly (and there's even an achievement related to that in the first game).
* ''VideoGame/{{Pac-Man}}'' is a cylinder, since you can only go between left and right. Some hacks implement vertical wrap-around, turning it into a torus.
* The eponymous TempleOfDoom in ''VideoGame/{{La-Mulana}}'' is [[http://en.wikipedia.org/wiki/Simply_connected_space non-simply connected]], almost certainly deliberately. If you try to make a map that shows where all the areas are in relation to each other, taking every connection into account, you'll quickly discover that it can't be done. In particular, it's not at all clear what the lowest point inside the ruins is.
* The Polyhedron in the Russian art-house game ''{{Pathologic}}''. From the outside, the building simply appears to be impossible. [[spoiler: The inside is implied to more or less be another ''dimension'', inhabited by hundreds of children suspended in some kind of weird dream world.]]
* In ''VideoGame/DiabloII'', the Arcane Sanctuary area contains some quite Escher-esque geometry: platforms are supported by pillars that stand on other platforms which ought to be at the same height. The game gives the option of displaying in perspective (parallel lines converge at the horizon) or isometric (parallel lines remain parallel). In Arcane Sanctuary, the perspective option is disabled, due to it being impossible to draw.
* Giygas' final form in ''VideoGame/{{Earthbound}}'' is fought inside what is best described as a "pocket dimension"... except Giygas' final form is also the pocket dimension itself. Rather fitting of Giygas, the TropeNamer for YouCannotGraspTheTrueForm.
* ''VideoGame/{{Echochrome}}'' is a puzzle game based on the works of Creator/MCEscher. The geometries are as weird as you might expect. To elaborate, in the game, you are allowed to "cheat" the laws of perspective because only the camera angle's perspective counts as "real". If there is a beam covering up a hole, the hole [[LogicBomb then ceases to exist.]] This is a necessary skill to guide the main character to safety. [[note]]You control the camera, not the player character.[[/note]]
* ''[[VideoGame/PokemonDiamondAndPearl Pokémon Platinum]]'': The Distortion World in AmazingTechnicolorBattlefield form. Made into MindScrew material thanks to the flat, unchanging background theme and the fact that there are no Pokémon in it at all except for Giratina. Not to mention the fact that ''holy crap the sky is upside-down.''
** Also "fun" in the fact that the direction commonly known as "up" seems to be on a drunken bender. Walking up and around walls and waterfalls is only the beginning...
** There's also the Lost Cave in FireRed and LeafGreen, in which it is possible to walk through a door, turn around, walk back through the same door, and find yourself in a room that is definitely not the one you started in.
** The Psychic move Trick Room...well, look at the description. "The user creates a bizarre area in which slower Pokémon get to move first for five turns." The user warps space so that going slower makes them move faster. That's pretty alien.
** In the Generation Six games...you can [[AndThatsTerrible MOVE DIAGONALLY!!!]]
* According to the characters, the Primeval Thaig in ''VideoGame/DragonAgeII'', although we have to [[TakeOurWordForIt take their word for it]], 'cause that's kind of hard to program.
* Certain areas in the ''Franchise/SilentHill'' series, usually paired with ChaosArchitecture; examples include but are not limited to: the girls' bathroom in [[VideoGame/SilentHill1 the alternate school]] which leads you to the second floor when you exit it, the door between the first and second floors in Nowhere, and the convoluted space-time of the alternate Lakeview Hotel in ''VideoGame/SilentHill2'', where the doors now teleport you around the building, and you have to find the correct one that will warp you to the otherwise inaccessible east wing. And going back in the same door leads to a different door than the one you entered. Not to mention the Historical Society, where you jump down several extremely deep holes, then take an elevator even further down, but when you come out of it on the lakefront, you're only about 20 feet below where you started. It also has Escher-esque architecture at points, e.g. the room with the hole leading to the prison (doors on the floor and walls), and the rotating room in the Labyrinth.
* The Daedric ruins in ''[[VideoGame/TheElderScrollsIIIMorrowind Morrowind]]'' fit this trope. They certainly weren't built by man or mer...
* It's possible to ''make'' these in ''VideoGame/DwarfFortress'' if you're careless, insane or second-hand enough. Case in point: [[LetsPlay Headshoots]] had rooms that ''the players couldn't find'' without zooming on a dwarf that happened to be in them. [[spoiler: The last survivor is holed up in one of them.]]
** Of course, rather disappointingly, there's nothing physically impossible about it — it's just a web of extremely convoluted tunnels.
* In ''GuildWars'', there is no in-game map showing the entirety of the Realm of Torment. There is a very good reason for this- direction and distance are coherent within regions of the Torment, but not between them.
* This is the whole point of the city of Sigil in ''PlanescapeTorment'': a city existing on the inside of a giant rotating torus. The streets move around when they feel like it and every opening bounded on at least three sides can potentially lead you [[CoolGate virtually anywhere]] (including somewhere you really don't want to go). One character talks about being transported by a hidden portal that consists of the archway that appears when approaching two trees from just the right angle. The city itself also happens to be floating at the ''top'' of a spire that is infinitely tall, which located directly in the ''center'' of a plane that stretches infinitely into all directions.
* ''VideoGame/{{X}}: Beyond the Frontier'' and its sequels plays it straight with "Spacial Compression" improving your cargo capacity.
* A wonderful example in text adventure ''Trinity'', which contains a Klein Bottle that you can walk through. After you do, east and west are reversed everywhere else in the game. This is useful for [[spoiler:turning a clockwise screw into a counterclockwise screw]].
* ''VideoGame/VisionsAndVoices'' has the mirror worlds. While they aren't that extreme, they can be pretty freaky — numerous characters react badly upon seeing them.
* The Milkman Conspiracy level in ''VideoGame/{{Psychonauts}}''. It's a brightly-colored American suburb with white picket fences, nice homes and topiary. Or at least, it sort of looks like one after being crumpled up like a ball of tin-foil, then stretched out into a rough hollow sphere, leaving all the wrinkles and tears caused in that process in the landscape. Gravity still seems to think it's normal, though - you're always drawn towards the floor. Even if, technically speaking, that direction isn't really ''down''.
* ''Videogame/{{Prey}}'' is based aboard a cybernetic moon size space ship where things like gravity and even space-time are not consistent. The player character occasionally remarks on this.
* A particular player-made map for ''[[VideoGame/FarCry Far Cry 2]]'' is shaped like a cube with two sides removed and tilted on its axis. Due to the inclines that a player is able to move on without sliding off or falling, the players can run on all four of the inner faces, even though they appear to be perpendicular without close examination. This leads to strange cases of a player standing on the wall of a building and firing at someone on the street ahead of them, which is going into the sky.
* The ''Zelda'' series pulls this off a lot of times in different ways. The most common is the classic Lost Woods. Take a wrong turn and you magically end up back at the start, even when it should be normally impossible. This happens in some other areas like Ganon's Tower in ''VideoGame/TheLegendOfZeldaTheWindWaker''.
** The Fairies' Woods in ''VideoGame/{{The Legend of Zelda Oracle|Games}} of Ages'', in which moving from one screen to the next and back again winds up placing you in a completely different spot than before.
** In the Forest Temple in ''[[VideoGame/TheLegendOfZeldaOcarinaOfTime Ocarina of Time]]'' there is a corridor which twists 90 degrees to the side, meaning you end up walking on what was originally a wall. One puzzle in the temple involves activating a switch that twists and untwists the corridor, so you can access different sides of the room. And you're still somehow oriented the same way relative to the rest of the dungeon.
** ''[[VideoGame/TheLegendOfZeldaMajorasMask Majora's Mask]]'' has a twisted corridor in the intro level. The Stone Tower is built on this - it involves reversing gravity so you can run around in the ceilings of rooms. This is made even more [[MindScrew mind-twisting]] by the fact that the horizontal orientation of the temple is preserved after it is flipped over -- i.e. a room on the right of the entrance normally would stay on the right of the entrance when flipped -- meaning the dungeon somehow ''inverted itself''. Even the Perfect Guide writers were confused by the whole thing.
*** Arguably the moon (which is about the size of a city) contains an endless field with a tree in the center.
** Arguably, Hyrule itself. Although the geography will remain consistent within a given game, titles which take place earlier or later on will be vastly inconsistent, often with only the exception of Death Mountain.
* ''SuperMarioBros'' - Warp Pipes ignore any physics beyond RuleOfFun, but the ones in ''[[VideoGame/MarioAndLuigiBowsersInsideStory Bowser's Inside Story]]'' ''really'' take the cake. There are multiple, microscopic pipes ''inside'' of Bowser that, without actually going ''through'' Bowser at any point, lead ''outside'' of Bowser, simultaneously increasing the size of those who go through them to macroscopic. Though it's impossible in-game, there is nothing ''in theory'' to prevent Bowser from entering one of these pipes. What would happen if Bowser did use such a pipe? Decent people shouldn't think too much about that.
** Well, remember: the reason they lead in and out of them is because they are "warp" pipes. They basically teleport the user to another pipe. There's always the possibility that [[SuperMarioBros World 1-2]] could be in another universe entirely...
* ''VideoGame/SuperMarioRPG'' seemed to parody video game wraparound: the overworld actually ''is'' donut-shaped, despite there being no real reason for it.
* ''VideoGame/SuperMario64'' has the endless staircase. However high you climb, the bottom is only a few feet behind you when you turn around.
* ''VideoGame/SuperPaperMario'' has a unique twist. Mario exists in a 2-D world (with {{Shout Out}}s galore to the first ''SuperMarioBros'' games), but the first ability Mario learns is to "flip" between dimensions. In other words, he ''gains access to the third dimension''. Now, this isn't any problem for the player, but what's this like ''[[FridgeBrilliance for Mario]]''? ...let's just say he needs a SanityMeter to stay in 3-D. However, the game is a sequel to the first two Paper Marios, which were in 3D. Mario also seems to handle switching between 2D and 3D just fine between games anyway.
* There's a game in development, called ''Miegakure'', in which the puzzle aspect involves a 4th spatial dimension. Just trying to visualize a textual description of the game mechanics is enough to cause a headache. A three-dimensional environment can be represented by multiple two-dimensional images. Imagine taking an object, and tracing its outline on a flat surface from each side. You can get a good idea of the actual shape of the object in three dimensions by putting those images together in your head. What Miegakure does is present a four-dimensional environment in a similar fashion, in a series of three-dimensional models. You can switch the "angle" from which you view the four-dimensional environment by hiding one dimension and causing another one to become visible, similar to how a flat picture of a three-dimensional object "hides" the depth dimension.
* The Bizarre Room in the Wonderland level of ''KingdomHearts''. Entering from different points of the world -- including the room itself -- leads to you stand on different dimensions of the room, i.e. the walls and roof. However, the dimensions of the areas you are entering ''from'' don't change at all.
** Castle Oblivion is suggested to have properties like this. In ''VideoGame/KingdomHeartsChainOfMemories'', it rearranges itself based on the memories of those that travel through it. In ''358/2 Days'', Organization XIII is scouring the place for a specific room but cannot find it anywhere, despite having used the Castle as a base for years at that point. Summed up nicely in this conversation:
-->'''Saix''': Did you search ''every'' room?
-->'''Axel''': Come on. You know as well as I do that's impossible.
* Two areas in ''[[Videogame/SubMachine Submachine: Subnet Exploration Project]]'' have rooms that connect in ways they should not. Appropriately, one of them houses a fan theory that the Submachine is looped through the fourth dimension, and the other is a series of padded cells. Another area is, for no apparent reason, sideways.
* In ''VideoGame/TheDig'', the architecture of the Cocytans shows a lot of reverence to the 5 Platonic solids, including shapes with strange symmetries; and there also the in-universe example of space-time six -- a 6 dimensional realm.
* The Mobius Ring track in ''VideoGame/{{F-Zero}} GX'' exhibits these; the sky is always up, as the mobius has only one side. Let's not talk about the architecture.
* An interesting loading error in ''VideoGame/IndianaJonesAndTheInfernalMachine'' once caused a corridor to loop back around itself into the same room that the player had just left without any perceivable distortion. The player who encountered the bug thought he might be going crazy at first.
* ''VideoGame/{{Minecraft}} on LSD'', the combination of 2 mods. Youtube it. Everything is still the same but looks extremely... peculiar. A straight line looks like a coiled rope, and then you imagine that these are supposed to be blocks doing this, but curving. And then you see the distance going on the ceiling... Although it's all visual (but can often feel like you're walking on a circular world and not a flat one) for now.
* Entering the main room of the Tremere chantry in ''VampireTheMasqueradeBloodlines'' is easy: just walk in the front door, go straight, take a left, a right, then another left. But try to reverse those directions to leave, and you end up back at the same place you started. Any wrong turn on the way out sends you back to the main hall, and the path out is not the same as the path in.
* Invoked in one of the epilogues in the game ''PrimalRage''. When you play as Vertigo, the epilogue says she forced enslaved humans to build a palace whose alien gemoetries drove the human workers insane. There's an illustration with it.
* ''VideoGame/TheGameOfTheAges'' introduces a fourth spatial dimension, which you learn to navigate.
* ''VideoGame/BaldursGate'': leaving aside all the bizarre dimensions and obscure dungeon twist you can encounter, Athkatla has a few doses of alien geography. Notably, no matter which way you approach the bridge from, you will always enter the district from the northern end. There are only two locations on the entire map located north of the Bridge District, and there are no other apparent ways across the river without hiring a boat.
* There's an old Russian [[GameMod mod]] of ''VideoGame/PrinceOfPersia1'', called ''4D Prince of Persia''. It takes advantage of the way room connections are programmed and creates levels where normal directions don't apply: Levels that loop and wrap around, corridors where running back doesn't take you where you came from, [[BottomlessPits infinite pits]]... The mod [[DownplayedTrope doesn't do it that much actually]] however; it only does it on palace levels, and leaves many levels unchanged. Then there are further mods ad level packs inspired by 4D, and they take the idea [[UpToEleven much further]].
* ''Videogame/{{Fez}}''. Gomez is a 2D man suddenly gifted with the ability to shift the 2D world on the third dimension.
** Even better, he has an ExpositionFairy following him around that's shaped like a tesseract (a 4-dimensional shape; it's the "next level" of the cube, much like the cube is the "next level" of the square). So he's a 2D man in a 3D world with a 4D companion!
* ''VideoGame/MondoMedicals'': The very first stage causes you to go in an infinite loop [[spoiler: unless you go the opposite of where the arrows tell you.]]
* ''VideoGame/{{ZZT}}'''s level editor allows any edge of any board to be connected to any other board, including itself, and the edge you enter a board from does not have to lead back to the board you came from. Game designers can easily abuse these facts to [[MindScrew mind-screw]] a player with maps that repeat and overlap themselves in nonsensical ways.
* Unintentional example in ''Videogame/GarrysMod''. Placing certain physics constraints on a prop can cause the [[WreakingHavok Havok physics engine]] to decide that within a single process tick, that a prop has ''infinite angles'' of orientation, which can cause some truly horrifying things to happen before the game either deletes the offending object or [[RealityBreakingParadox implodes on itself]] and crashes.
* ''VideoGame/CliveBarkersUndying'': Mostly happens in Oneiros, but some parts of the manor also feature this. For example, when exploring the Widow's Watch (located in the east side of the manor), you end on the great hall (placed in the west side). This was intentional, according to WordOfGod.
* In ''VideoGame/ShinMegamiTenseiIIINocturne'', a certain corridor in the Fourth Kalpa of the Labyrinth of Amala is known as the Twelve Meters of Eternity. It's a perfectly straight tunnel with no side exits. Somehow, depending on Kagutsuchi's phase, it leads to four different chambers. Samael is fought in the Diet Building's main stained glass room, warped to keep spinning in an impossible axis. Likewise, the warp points between each Kalpa ''seem'' to be freefalls, but have so many bends and curves, it's really not likely they end up following a single gravity point.
** In ''VideoGame/ShinMegamiTenseiIV'', Domains are the result of a demon folding reality to create a minor trap hole for unwary humans (slightly BiggerOnTheInside), with AlienGeometries rendered as walls of demonic flesh twisting in ways they shouldn't. [[spoiler:The largest Domains, Lucifer Palace and Purgatorium, are unspeakably vast and complex (they have their own ''skyline'', though they are concealed within, respecively, Camp Ichigaya and Naraku, ''neither of which is large enough to remotely fit them inside'').]]
* ''VideoGame/MonumentValley'' has this in the form of "Sacred Geometry". The protagonist spends the entirety of the game navigating and manipulating paths in ''Creator/MCEscher''-like ruins.
* ''VideoGame/DarkSoulsII'' for better or worse, has been noticed for using "impossible space". Of note is the transition from Earthen Peak to Iron Keep. The former is a vast valley of barren land with windmills and a poison soaked sky. At the end of the area you take an elevator to...a vast volcanic land with buildings melting into the lava below. Keep in mind that there is nothing in Earthen Peaks even hinting at this place being above it.
* The very first ''{{Castlevania}}'' game Vampire Killer unintentionally had this. Since it was on the primitive MSX computer, the entire castle consisted of static screens; instead of scrolling you simply used one of the exits to go to another screen. Unfortunately not all of the rooms were connected together properly. There are several cases where when you attempt to return to a previous room by using that room's entrance you'll end up in a completely different room.
[[/folder]]

[[folder:Visual Novels]]
* A minor example in ''VisualNovel/DanganRonpa'': The swimming pool occupies a space one story above the floor of a multi-leveled gymnasium. This trope is implied, though it may be due to lack of consideration on the creator's part.
* ''VisualNovel/{{Demonbane}}'', being derived from the Cthulhu Mythos, has this at several points. The characters describe the Deep Ones' artwork as "unpleasant" and headache-inducing, though they cannot say why, exactly. Later, the towers of R'lyeh are described as being "twisted in straight lines", with the protagonist {{Lampshading}} how that doesn't make any sense.
[[/folder]]

[[folder:Webcomics]]
* In ''Webcomic/EightBitTheater'', Black Mage's face is apparently so hideous as to be non-Euclidean—the hat keeping his features in shadow prevents people from [[GoMadFromTheRevelation being driven insane just by looking at it]], as seen [[http://www.nuklearpower.com/2001/06/18/episode-044-what-the-hell-just-happened-in-survivor-8-bit-style-part-9/ here]]. A more recent strip implied that revealing himself would ''[[http://www.nuklearpower.com/2008/01/05/episode-939-total-protonic-reversal/ destroy the universe]]'', but this was just an idle daydream.\\
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When the Light Warriors enter the [[TheVeryDefinitelyFinalDungeon new-and-improved Temple of Fiends]], Black Mage criticizes it's infantile sense of twisted geometry (The room is merely upside-down for no reason), claiming that to "draw out ancient and malevolent forces of the underverse" you need to "[[http://www.nuklearpower.com/2008/06/12/episode-1004-fun-house/ start with parallel lines that intersect]]".
* In ''Webcomic/{{Adventurers}}'', [[http://www.adventurers-comic.com/d/20020614.html when Imposis is just about to leave]], Ardam points out that nothing he does seems particularly impossible. Imposis gives him a Penrose triangle and continues on his way, leaving Ardam to hold it in his hands and stare at it until he gets a headache.
* ''ChainSawSuit'': [[http://chainsawsuit.com/2010/05/12/cthulhu-cheats/ Cthulhu gets caught using non-Euclidian dice during a game of]] [[TabletopGame/DungeonsAndDragons Humans and Habitats]].
* A few arcs in ''{{Fans}}'' (notably the whole of Book 5) centered around a power-object called the 23-Sider, an RPG die with 23 identical sides. When the 23-Sider was formed in Book 5 it warped reality.
* ''Webcomic/GunnerkriggCourt'', In Chapter 19: ''Power Station'', the buildings at [[spoiler:Zimmingham]] look pretty normal from nearby, but [[http://www.gunnerkrigg.com/archive_page.php?comicID=461 long-distance shots]] reveal that they are at crazy angles relative to each other.
* In ''Webcomic/{{Homestuck}}'', the evil planet of Derse (and presumably, its good counterpart, Prospit) has inner depths and corridors that twist upon themselves in ways that challenge the rational mind, as shown in [[http://www.mspaintadventures.com/?s=6&p=003568 this sequence]]. It is clearly not just a bunch of buildings built around a central point. The core of its moon is hollow, and there it can be seen that the moon is somehow held together by chains that are loose and just float there.
** [[http://www.mspaintadventures.com/?s=6&p=004942 The final form that Skaia takes as well.]]
* ''Webcomic/ProblemSleuth'': You cannot descend into the sky because the universe is not upside-down!
* According to ''QuestionableContent'', [[http://questionablecontent.net/view.php?comic=1380 dildos]] can have alien geometries too.
* Pip in ''Webcomic/SequentialArt'' chose to prove his superiority in [[BlandNameProduct Cubeminer]] by building "[[http://www.collectedcurios.com/sequentialart.php?s=684 Escher's Staircase]]". The next page shows that with a few tweaks you sometimes can build ''this'' in a 3D game. [[spoiler:But there's no guarantee that the physics engine will survive an attempt to process it.]]
* From ''TalesOfTheQuestor'', we have the ''[[http://www.rhjunior.com/totq/00513.html Unseleigh castle...]]''
** Yet another homage to Creator/MCEscher's "Relativity".
* The polygons in ''TriangleAndRobert'' tend to have their own style of geometry, leading to strips like [[http://tr.froup.com/tr.pl?412 this]] or [[http://tr.froup.com/tr.pl?2327 this]].
* The Toymania store that serves as the main setting for ''TRULifeAdventures'' is bigger on the inside than it is on the outside. Subverted, though, in that it's a fluke of how the measurements were taken.
* The author of ''Webcomic/{{Xkcd}}'' drew a comic about [[http://www.newyorker.com/online/blogs/cartoonlounge/2008/10/cartoonoff-xkcd.html hyperbondage]] (see slide 5) for a cartoon-off against Farley Katz.
* In ''TheInexplicableAdventuresOfBob'' the alien Nemesites know how to make buildings that are bigger on the inside. [[GeniusDitz Molly]] describes such a building as "all tesseracty and [[Series/DoctorWho Whovian!"]] This becomes a plot point when that building is destroyed, and all of its chunks of debris expand outward and fly ''away'' from each other as they "drop into normal spacetime.'' This saves a character who was trapped inside from being crushed.
[[/folder]]

[[folder:Web Original]]
* Doctor Ka's mansion in the ''GlobalGuardiansPBEMUniverse'' is effectively a [[http://en.wikipedia.org/wiki/Tesseract tesseract]], and is definitely [[BagOfHolding bigger on the inside]] than on the out. If its layout was drawn on a set of blueprints it would feature rooms that overlapped spatially, rooms that seemed to have no exits or entrances, spherical rooms that nonetheless had corners, and rooms where the plane of gravity depending on which way you were looking.
* ''Wiki/SCPFoundation:'' [[http://scp-wiki.wikidot.com/scp-033 SCP-033]] is a missing integer. Any surface it's written on will begin to break down.
-->'''Prof. █████████:''' We know that after 2 comes 3 and after 3 comes 4. What this formula proves is that we missed a number somewhere. Imagine if all our technology was based on the belief that after 4 came 6. We simply didn't know or conceive of 5. That is in essence what this formula proves. We missed a number. ... I don't think it "destroys" anything. I think it tries integrating itself into our system and our system can't hold it.//
** [[FridgeLogic Wouldn't this just be Base 11?]] A concept which computers can certainly handle...
*** I made the assumption that the number was "imaginary," at least as far as we could understand it. It's a number that shouldn't exist. Instead of Base 11, think Base Tangerine Breeze. MindScrew, anyone?
* ''Literature/FineStructure'' describes universes with more dimensions than our this way.
* ''WebOriginal/ProtectorsOfThePlotContinuum''
** The PPC Headquarters. It is unclear whether it is just a confusing maze of a building or whether it can actually move around, but thanks to the Laws of Comedy, one of the only ways to find the place you are trying to go is to distract yourself and not think about it. However, it "was" built by alien plants, and they seem to be able to navigate it just fine.
** Also, poorly-constructed descriptions in the Word Worlds cause some rather eye-breaking visuals for the agents when the worlds try to put them into practice. In one mission, Agents [[TemptingFate tempted fate]] by saying "It's a wonder we're still in three dimensions."
* Buildings frequented by [[Franchise/TheSlenderManMythos the Slender Man]] often develop these, sometimes reaching full-blown EldritchLocation levels. Don't expect a door to lead to the same room it did two minutes again.
** ''WebVideo/MarbleHornets'': When Jay investigates Alex's abandoned house near the end of season one, he gets bounced around between rooms and eventually finds himself in the disused bathhouse from an earlier entry. [[spoiler: The next entry shows something similar happening in ''his house''.]]
** ''WebVideo/EverymanHybrid'': the cast is out on a hiking trip in the middle of a bright, sunny day, exploring an old abandoned house in the middle of nowhere, deep in a wooded area. A door in the basement of the house leads to a sprawling beach in the middle of the night. In a later episode, they find a crawlspace in Jeff's house that leads them to the aforementioned abandoned house miles away. Later still, Vinny finds a house that either warps him to different parts of the cast's homes, or is an equally weird mishmash-ed replica. That last one gets even weirder later on, when Vinny suggests [[spoiler: he and his friends are fictional constructs and their "houses" have always been like that.]]
** Appears a couple times in ''SevenshotKid''. Usually it serves as a prelude to something horrible.
** The HellHotel in the HalloweenEpisode of ''WebVideo/TribeTwelve''.
** ''WebVideo/OneHundredYardStare'': When Avery, Macy, and Ellie first run from the Slender Man there is a good dosing of this, with them starting in a yard of some sort and ending up, after a jaunt in a building, next to a moving train.
* The Metal Glen from ''Roleplay/RubyQuest'' displays aspects from this. First there's the metal shutter in Ruby's room, which sometimes opens to a window and sometimes to a passage. Then half of the Brig turns upside-down, gravity and all. Then it gets weirder.
* ''TheDionaeaHouse''. All of them. The one in Boise, for example, has a second floor that is not visible from the outside. It says something that [[PeoplePuppets this is]] [[GeniusLoci not the]] [[ImAHumanitarian strangest thing about it.]]
* Carmilla's room in the ''Literature/WhateleyUniverse''. It keeps changing size and shape. Its door moves from building to building. It's possible to walk in and out of it without using any known entrance. There's a reason the staff at Whateley Academy calls it the [[Creator/HPLovecraft H. P. Lovecraft Room]].
* There is no geometry but TimeCube. You are educated stupid. Time Cube is so obviously true that knowing anything except Time Cube will drive you crazy when compared to Time Cube.
* ''Franchise/TheFearMythos'' has The Empty City, also known as the City of Empty Shadows or [[NamesToRunAwayFromReallyFast DEVOURER]]. It's a [[GeniusLoci living city]] which intentionally makes itself into AlienGeometries in order to make sure its victims stay within it until they die. [[AndIMustScream Or worse.]]
* Fredrik K.T. Andersson managed to [[http://andersson.elfwood.com/Naught-or-Cross.2524315.html invert this]].
* ''{{Bravemule}}'', the saga of a ''VideoGame/DwarfFortress'', gave the dwarves an utterly bizarre culture with BlueAndOrangeMorality. Among other things, any shape that is not rectangular is "unscrupulous". An accidentally-created ''octagonal'' room was thus treated as horrible and incomprehensible, giving dwarves {{Catapult Nightmare}}s and such.
* ''Wiki/TVTropes'': The InvertedTrope example on PlayingWith.MileLongShip. How exactly do you get a ship whose length is a negative number?
* In ''Podcast/WelcomeToNightVale'' the station management room is, as far as they can tell, too large to fit in the radio station building.
** Intern Dana ends up stuck in the forbidden dog park (Do not take your dog to the dog park. Do not go to the dog park. Do not look at the dog park. Do not think about the dog park.), and notes that although it looks like it's the size of a city block when you're standing still, she was able to walk along one of the black walls that surround it for two weeks without reaching a corner.
** When Dana gets stuck in the desert other-world, she gets trapped in a geographic loop; no matter how long she walks, or in which direction, she always finds herself heading towards the mountain with a blinking red light. Incidently, children in Night Vale are taught in school how to deal with geographic loops, using a simple memory device: '''knife'''.
** Don't forget the House That Doesn't Exist. It ''seems'' like it exists, like it's just right there when you look at it, and it's between two other identical houses, so it would make more sense for it to be there than not, but...
[[/folder]]

[[folder:Western Animation]]
* ''WesternAnimation/BatmanTheBraveAndTheBold'' has a standard-issue Escher magical library in the BatmanColdOpen of "The Eyes of Despero". Batman is largely unfazed by the shifting gravity, and actually uses it to good effect.
* The ''Foghorn Leghorn'' cartoon "Little Boy Boo" plays this for laughs. Foghorn is playing hide and seek with a child genius and hides in the coal bin. The kid performs a few calculations and then ''digs Foghorn out of the lawn''. A very befuddled Foghorn protests that he was in the coal bin, but the kid just shakes his head and holds up the calculations. Foghorn then goes to look inside the coal bin, but decides "No, I'd better not look. I just ''might'' be in there."
* The titular ''WesternAnimation/FostersHomeForImaginaryFriends'' sometimes exhibits a non-malevolent version of this combined with BiggerOnTheInside. In one episode, Mac is attempting to leave for dinner from the houses roof, but they go down a flight of stairs and through a door to end up back on the roof (prompting Mac to confusedly remark "[[HowIsThatEvenPossible But we went]] ''[[HowIsThatEvenPossible down]]''."). They later fall down a trap door from somewhere in the middle of the house, sending them back to the roof ''again'', and Mac declares "This is downright unnatural."
* Comic example: the Flanders's rebuilt house in ''TheSimpsons'' episode "Hurricane Neddy" features many impossible features.
* In the ''WesternAnimation/AdventureTime'' episode "The Real You", Finn uses his magically-granted super intelligence to create a fourth-dimensional bubble. It looks like a cube wire-frame constantly inverting itself (a tesseract) before it collapses into a black hole.
* Soviet short animated film {{WesternAnimation/Pereval}} featured graphics by practicing topologist A. Fomenko.
[[/folder]]

[[folder:Real Life]]
* [[http://physicsworld.com/cws/article/print/23009 Studies]] of the cosmic microwave background radiation suggest that it better fits a Poincaré dodecahedron than a sphere.\\
\\
To make the Poincaré dodecahedron more clear: you are floating inside a giant dodecahedron (a 12-sided polyhedron). When you get to an outer face you WrapAround to the opposite face. Except the faces don't exactly line up, so you also rotate one tenth of a rotation.\\
\\
More aptly, it is to be observed that Euclidean geometry, mathematically speaking, is a ''special case'': it only applies to forms in a space with zero curvature (for the two-dimensional case, a perfectly flat plane); something that is, strictly speaking, an abstract concept (in light of the fact that time and space are demonstrably ''curved'' by gravity.) Consider that you cannot, in Euclidean geometry, draw a triangle with three right angles, ''but it is perfectly possible on the surface of a sphere.''\\
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Sometimes made worse by the fact that a non-Euclidean two-dimensional geometry is often ''visualized'' as embedded within a three-dimensional Euclidean space (the surface of a sphere, or a saddle), which leads some people to mistakenly believe that an n-dimensional non-Euclidean space ''requires'' an unseen n+ 1 dimensional space. (It's not too difficult to imagine a two-dimensional space with positive curvature as the surface of a sphere. Now try to wrap your mind around the idea of a space where the geometry works out the same as it would on the surface of that sphere, but without any third dimension at all.)\\
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There are five axioms used to make geometry. Change one, and you get non-euclidean geometry. Change all five, and you could very well get arithmetic. Calling it a special case is an oversimplification.\\
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Speculations on the Topology of the Universe aside, it's clear, and even somewhat well known, as stated above, that the effects of gravity are described by the curvature of spacetime, which means that in truth, geometry is not Euclidean at all. As a famous test of this, we can see stars which should be hidden behind the Sun during a solar eclipse, due to the light following the shortest path in curved space towards us. Time is also curved, in a sense, as clocks will run slower in places where classically the gravitational potential is lower relative to clocks at greater potential. This effect too, was measured using high precision atomic clocks.\\
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Some astronomers who like thinking outside the box suggested that one might put a satellite 550 AU away from the sun. At this point, the aforementioned curvature of the spacetime bends light just right, making it possible to use the sun itself as, essentially, ''the primary lens of a huge gravitational telescope''. This idea is called a solar foci telescope.
* Spherical geometry isn't just something for universe-scale models. The ''surface of the earth'' is represented as a two-dimensional non-Euclidean space every time you look at a map. As mentioned previously, a sphere can have a triangle with three right angles on it, and the earth is (approximately) a sphere.
** An example: Start at the north pole. Go to the equator. Turn right 90 degrees. Continue along the equator. Turn right 90 degrees. You will reach your starting point. [[http://upload.wikimedia.org/wikipedia/commons/9/97/Triangles_%28spherical_geometry%29.jpg Nifty, huh?]]
*** Right angles aren't really anything special. The issue is that a 90-degree angle only looks like two perpendicular lines intersecting at a point on a flat two-dimensional plane. Angles have a problem in 3-D space...they ignore the z-axis (depth). Lines are only perpendicular on the same plane.
* Many implementations of [[TheGameOfLife Conway's Game of Life]] wrap the edges of the grid, so the cells technically live on the surface of a torus. Or in the case of a 3D implementation, a hypertorus.\\
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Some starfield simulators do this, too. Stars that vanish off one edge of the volume of space appear at the opposite one, resulting in the stars being positioned on the 3D surface of a 4D torus.\\
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These wraparound connections are used in the communications paths for processes or threads in some concurrent programs.
* There are multiple projections used on pictures, most commonly the gnomonic projection. The fisheye projection is also well-known. The reason these are necessary is that people see in elliptic geometry. As a simple example, imagine that you are standing on a railroad track, facing along the track. If you look straight down, the rails will look parallel, but if you look straight forward, they will intersect. If you look halfway between, you should be able to see where they're parallel and where they intersect, despite being perfectly straight.
* Relativistic physics border that territory at times. e.g length contraction says when moving at a high enough speed there is a visible decrease in lengths (the length decrease is always there, just you can not see the difference caused by sqrt(1-(v/c)^2)). That is still believable if you have some fantasy. The trouble is, from the other point of view the not moving system is the one shortened. Better not try it yourself.\\
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To clear the confusion (as much as possible, anyway), if things are moving, they are shortened in the direction of their motion by a numerical factor dependent on their velocity. If you measure the length of an object at rest you will always find it is greater than the length of the same object moving at a finite speed with respect to you. Of course, in said object's reference frame, it is by definition at rest, and it is ''you'' who is moving, and therefore, shortened.\\
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The perceived contraction of length is connected to the relativity of simultaneity, the fact that events which are simultaneous for one observer (person) can be not simultaneous for other observer. To measure length you have to mark where beginning and end of said length are at the same time; for observer moving with relativistic speed it would look like one first marked beginning, then end (after it moved).\\
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The distance that the distance one through spacetime, the spacetime interval, is of a constant length, and is determined by the formula s = sqrt(x^2 + y^2 + z^2 - (c*t)^2). That is to say, although space contracts by a factor of sqrt(1-(v/c)^2)), time expands by an equal factor, so the spacetime interval that you cross remains constant. This means that the velocity of the thing that travels along the interval is already determined for any given observer. For the layman, this means that objects do not really shrink when you travel at velocity; they are actually just rotating in four dimensions, and just appear to shrink because we can only see in three dimensions.
** And that's just special relativity. General relativity predicts that objects in a gravitational field shrink relative to those outside of the field. Essentially, when looking from the outside in, massive objects like stars or planets are actually BiggerOnTheInside. This is due to the fact that what we experience as gravity is actually the mass of planets causing space to shrink in its presence. This means that straight lines, like those of laser light, become bent in the presence of mass. This is why planets orbit other planets, and light gets bent in a gravitational field: they are following the curved lines of space around the planet. The best analogy of this is placing a mass on a rubber sheet, and watching it deform the rubber around it. Letting a ball spin around the mass is rather similar to planets orbiting one another, as the balls just follow the curved paths of the rubber sheet.
** [[http://www.youtube.com/watch?feature=player_embedded&v=JQnHTKZBTI4 Gaze upon the optical effects of special relativity.]] Drugs ''wish'' they could do this.
* The Bermuda Triangle, according to many theories and reports. In addition to vehicles vanishing without trace (no wreckage left), reappearing after disappearing from radar, etc. some people have reported experiencing "time warping" or "missing time" while traveling through here.\\
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In reality, while several accidents have taken place there, they're not statistically more common than in any other area of sea with the same density of traffic. Which, in spite of the stories, is considerable.
* The Mandelbrot Set is a two-dimensional slice of a four-dimensional object that represents the eventual fate of iterating the assignment z <- z* z + c, where z and c are complex numbers (two dimensions each). Start with z=0 and try different values of c, and you get the usual two-dimensional view of the Mandelbrot set (which is, properly, only the ''boundary'' of the usually-black region representing points that do not escape to infinity). Fix a value for c and try different starting points for z, and you get a Julia set. The complete four-dimensional object stacks all the two-dimensional Julia sets along a complex dimension for a total of four real-valued dimensions.
* A [[http://en.wikipedia.org/wiki/Tessaract tesseract]] is a "four dimensional cube". Just as a square is only one face of a cube, a cube is only one "face" of a tessaract. [[YourHeadAsplode Think about that for a second]]. The vertex of the tesseract is adjacent to four edges, the vertex figure of the tesseract is a regular tetrahedron. The dual polytope of the tesseract is called the hexadecachoron and... [[AustinPowers oh no I've gone cross-eyed.]]\\
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Scarier still, people have built computer models Rubix Hypercubes which people have successfully solved. [[http://www.superliminal.com/cube/cube.htm For your headache-inducing pleasure]]. [[http://www.gravitation3d.com/magiccube5d/ A 5D version has also been made.]] And then a guy got to '''[[http://astr73.narod.ru/MC7D/MC7D.html seven]]'''...\\
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If you want a quick view of just how confusing tesseracts can be, see [[http://www.youtube.com/watch?v=6xrSvVEpOog&NR=1 here]]. Lovecraft would be proud. (Or actually he'd probably be nihilistically horrified at the alien, inhuman cosmos revealed by science, but whatever.)\\
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Tesseracts are really just the start of a really long and dark journey. Even a [[http://en.wikipedia.org/wiki/Hilbert_cube Hilber cube]] is a really simple example when compared to some of the ''other'' stuff. It is also a cuboid of countably infinite dimension. Studying maths at uni sort gets you used to this stuff...
* [[http://www.urticator.net/maze/ Try solving a 4D maze.]] Just 3*3*3*3 takes about half an hour, and that's if you've gotten used to moving around in 4D.
* Try wrapping your head around the Moebius Loop. It's a loop with a half-twist with only one side and one edge. Similarly, the Klein bottle, which is a closed surface and only has one side, rather than having an inside and an outside. It has to go through itself at one point to make that work, though.
** Not really, that is just an artifact of embedding it in 3d space, in proper 4d space there is no such intersection.
* In 3d animation programs, when you make a polygon it's usually supposed to have 4 sides at the most and flat. In Maya, if you have something with more than four sides, edges that don't connect to a vertex or a vertex that's not connected to an edge, things get...weird. You end up with a shape that the program can't draw properly that will usually look like a different surface depending on where you happen to be viewing it from.\\
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Programmers tend to do things like this a lot when they first step into the world of [=OpenGL=] and [=DirectX=]. Get the position of a vertex wrong when you're just messing around with increasingly more complex shapes, and you can easily find yourself with a headache just from looking at the shape you've made. This effect is how the Alien Geometry corridor in Legend of Zelda: Ocarina of Time was implemented. Some corridors in the ''{{Descent}}'' series are also twisted like this.
* Higher doses of LSD can produce visions of impossible shapes.
* UsefulNotes/{{Pittsburgh}}, Pennsylvania's downtown area is called the "Golden Triangle" and is indeed triangular. To the uninitiated, though some of the turns ''feel'' like 90 degrees as you're trying to navigate. Making three "turns" and ending up back where you started has flummoxed more than one out-of-town driver (and more than its share of locals, too).
** [[http://drboli.com/2012/09/25/ask-dr-boli-168/ One Pittsburgh native]] suggests that in order to truly understand the city's geometry, eleven-dimensional string theory may be necessary.
* [[http://www.reddit.com/r/askscience/comments/f1lgu/what_would_happen_if_the_event_horizons_of_two/c1cuiyw?context=2 This Reddit comment]] is a fictional yet real physics-based story that illustrates just how nefarious black holes are.
** While the main point (the fact that all trajectories point to the singularity) is correct, an observer would *not* see the universe outside the black hole as if they had tunnel vision. This is a result of falling through the black hole ''making an effort not to fall'', i.e., with your engines on. Then the tunnel vision would be the result of relativistic beaming, not the fall. This site contains a much more accurate account, with a video: http://jila.colorado.edu/~ajsh/insidebh/intro.html
** Also, the article correctly notes that once inside the event horizon, all points outside lie in the past. However, it then proceeds to draw incorrect conclusions from it. You would not be blind inside the horizon, because far from not being able to see into the past, you can ONLY see into the past. When you see something, you see it not as it is at that moment, but rather what it was when the light reaching your eye was emitted from it. Furthermore, a Faster-Than-Light drive would not be prevented from escaping from a black hole, because such a drive is perfectly capable of traveling into the past as measured by certain frames of reference.
* "Mystery spot" attractions use tricks of architecture to simulate this trope. Gravity hills do the same thing, but with natural tricks of topography.
* Optical illusions can convey an impression of AlienGeometries, by [[MindScrew playing tricks]] on how the brain's visual association area interprets perspective from proportion and shading.
* [[http://www.youtube.com/watch?v=BVVfs4zKrgk How to turn a sphere inside out.]]
* How about an alien colour? Pink is a purely mental perception of a mix of red and violet light that doesn't actually exist on the visible spectrum. To an alien or whatever, it might look as though all of our little girls are engaged in [[GirlScoutsAreEvil some creepy cult!]]
** To clarify this, the [[http://en.wikipedia.org/wiki/Color_wheel color wheel]] isn't accurate. The visible spectrum goes from infrared into red, and from violet into ultra violet. Because they are at opposite ends of the spectrum, red and violet don't actually cross the way the color wheel suggests they do. That fade between them that we see as a specific color (pink) is all in your head.
** Pink is what's called a non-spectral color. Other non-spectral colors include the grayscale colors and mixtures of such with other colors, and what's called the line of purples. As the name implies, non-spectral colors have no unique frequencies in the visible spectrum, and exist as a perception of multiple frequencies.
** [[http://en.wikipedia.org/wiki/Imaginary_color Imaginary colors]] are even stranger. These are colors we could see, but no light can ever make.
** [[https://en.wikipedia.org/wiki/Impossible_colors Impossible colors]] (not to be confused with the above) are some sort of inversion of imaginary colors. They are specific combinations of existing hues that would mix to something that isn't a "full" mix of the two when viewed by a standard human. An example would be blue-yellow. When mixing paints of the two, [[https://en.wikipedia.org/wiki/RYB_color_model this makes green.]] When mixing lights, [[https://en.wikipedia.org/wiki/RGB_color_model they combine into white.]] However, when using some kind of mind trick such as crossing your eyes on a certain image (which is available in the page for impossible colors), it is possible to mentally see a color that looks part-blue and part-yellow.
* Both Google Earth and Apple Maps provide a 3D representation of the Earth's surface, made up of a combination of 2D aerial photos and 3D topography information. Sometimes disagreements between this data result in images of melting trees, spaghetti-like roads, bizarrely deformed buildings and more. See: [[http://www.postcards-from-google-earth.com/ Postcards From Google Earth]], [[http://news.cnet.com/8301-17938_105-57591342-1/the-glorious-glitches-of-apple-maps/ Glitches in Apple Maps]].
* [[https://en.wikipedia.org/wiki/Gabriel%27s_horn Gabriel's Horn]] is a geometric figure that has a finite volume, but infinte surface area.
* In [[https://en.wikipedia.org/wiki/Ultrametric_space ultrametric geometry]], all triangles have two sides of the same length, repeatedly moving a short distance doesn't result in moving a longer distance (no matter which direction you move), and every point inside a ball is its center.
* Anecdotal accounts of dreams suggests that the parts of our brain in charge of three dimensional space and short-term memory don't work all that well when we're asleep, resulting in passages to nowhere, doors that weren't there before (or the "there was a hole here, it's gone now" effect), or sudden jumps in physical location.
* [[http://www.geometrygames.org/CurvedSpaces/index.html Curved Spaces]] is a program that shows off quotient spaces of manifolds of constant curvature. One of the simpler ones is a dodecahedron where each of the pentagons is made entirely of right angles.
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