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[[caption-width-right:320:[[http://www.teamfortress.com/post.php?id=3368 We hardly knew ye.]]]]

->''"'Last version was better,' says Floyd. 'More bugs. Bugs make game fun.'"''
-->-- ''VideoGame/{{Planetfall}}''

%%NOTE TO EDITORS: If there is not a subpage for genre, examples should be placed in the respective folder on this page.

Some software glitches are so weird and wonderful that everyone likes them and looks back upon them fondly.

There are two common breeding grounds of popular bugs. One is 8-bit and 16-bit consoles where the code, data and game state are stored in one homogeneous block, and a single misplaced pointer can read sound generation code as level data or write the graphic memory to the player inventory. The other is cutting-edge 3D games where half a dozen third-party renderers, physics engines and net codes can conflict with one another in freakish ways.

If a Good Bad Bug is liked ''enough'', it may become an AscendedGlitch. {{Game Breaker}}s, while amusing, may be fixed to prevent GameplayDerailment. In some games, the bugs are a major draw for the game, which can lead to claims of ILikedItBetterWhenItSucked if removed.

If it's related to some game character somehow staying alive, it's DeadCharacterWalking.

Subtropes include MinusWorld and TheMissingno Contrast GameBreaker, as well as {{Game Breaking Bug}}s that may not overlap with the former. They are [[NotTheIntendedUse often helpful to]] {{Speedrun}}ners. [[IThoughtItMeant This trope has nothing to do with friendly cockroaches and mosquitoes,]] [[WesternAnimation/BugsBunny or a certain cartoon rabbit]].


* GoodBadBugs/ActionAdventure
* GoodBadBugs/DrivingGame
* GoodBadBugs/FightingGame
* GoodBadBugs/FirstPersonShooter
* GoodBadBugs/MassivelyMultiplayerOnlineRPG
* GoodBadBugs/{{Mech}}
* GoodBadBugs/PlatformGame
* GoodBadBugs/RealTimeStrategy
* GoodBadBugs/RolePlayingGame
* GoodBadBugs/{{Roguelike}}
* GoodBadBugs/SimulationGame
* GoodBadBugs/SportsGame
* GoodBadBugs/SurvivalHorror
* GoodBadBugs/TurnBasedStrategy
* GoodBadBugs/WideOpenSandbox
* GoodBadBugs/MiscellaneousGames


[[folder:Action Games]]
* ''VideoGame/{{Paperboy}}'', the coin-op version, had a race where you tried to get through a timed game. At the end of the race, you're supposed to cross the finish line. Here's where the bug comes in: if you cross just off the edge of the finish line outside of the edge but before the hedge of the game, it switches to an inverted video version of the race you just ran. This game normally has a high score of around 50,000, but the scores for things you hit in this strange area are way out of range, making it possible to get a score of around a billion, so high it can overwrite part of the screen.
* ''VideoGame/{{Castle Crashers}}'' had a glitch that would cause the boomerang to get stuck on any three bosses if the boss was between you and it. Since experience points are given based on how much you hit an enemy and not how much damage you deal, and the boomerang does 1HP damage per hit, the stuck boomerang would rack up hits and increase your experience quickly. A patch fixed this, but replaced it with a completely different Good Bad Bug that made the Boomerang able to demolish any destructible barrier in one throw.
* The video game adaptation of ''[[Franchise/{{Spider-Man}} Spider-Man 2]]'' allows you to fly into the stratosphere if you're hit by the train.
* In ''New VideoGame/RallyX'' (or at least the Xbox Live Arcade version), a glitch can cause you to go onto the walls. This can sometimes end up saving you, as the CPU-controlled cars can't get you there.
* ''VideoGame/{{Bayonetta}}'' has a rocket launcher, which is very powerful but slow firing. The bug is exploited by putting her claw weapon in lightning mode on her feet in the first weapon set and the rocket launcher on the second. Then just use the [[SpamAttack rapid-fire kick attack]] of the lightning claw and [[RealTimeWeaponChange switch weapons]] after the animation starts. Bayonetta will continue to do the claw kick animation and fire the rocket launcher with every kick for massive damage.
* ''VideoGame/{{DmC Devil May Cry}}'' has multiple glitches that make Dante fly around the screen avoiding enemy attacks, bosses that are unwilling to attack or are just paralyzed. The fandom decided to use them [[http://www.youtube.com/watch?v=pFLUE2kdemE to have fun.]]
* In ''Anime/DragonBallZ: Buu's Fury'', you can eat a Senzu Bean before you give it to someone for a quest. Does this mean the game wants you to get another one? No, it'll just take the one you don't have, which gives you [[UsefulNotes/PowersOfTwoMinusOne 255]] Senzu Beans.
* In ''VideoGame/ShadowTheHedgehog'', during the Hero missions a secondary character follows you around, and a second player can plug in a controller and control that character. In the Lost Impact stage, while Shadow is riding the Gun Rail he apparently loses his FriendlyFireproof status, as the secondary character (who is [[DeathByOriginStory Maria]], no less) can slap Shadow out of the cockpit, causing an ''explosion'' and making you lose rings.

[[folder:Adventure Games]]
* In ''SherlockHolmesNemesis'', the player, as Holmes, must have his companion Watson with him, of course. Unfortunately (or hilariously), instead of simply having Watson walk behind you, the game engine never has him actually move. Instead, he simply appears to soundlessly teleport right back next to you whenever you're not looking. [[http://www.youtube.com/watch?v=13YlEPwOfmk A hilarious YouTube video illustrates the problem.]]
** And the creepy implications of this behavior inspired [[AscendedGlitch Slender, and thereby the whole genre of stalker survival games]].
* Creator/{{Infocom}} games, being text-based, have some of the most [[http://graeme.50webs.com/infobugs/index.htm amusing glitches]] in gaming, as your mind can fill in ridiculous blanks to make them seem more ridiculous. Some gems include: poking the idiot in ''Arthur: Quest for Excalibur'', causing him to drop dead and losing you the game; giving robotic commands, even suicidal ones, to the humans trying to kill you in ''VideoGame/{{Suspended}}''; shadowing a murder victim only to have her disappear and her body appear from nowhere in ''The Witness'', and throwing body parts, like your hands or head, across the room in ''VideoGame/PlunderedHearts'', leaving them lying there on the ground where you can't retrieve them.
* ''Sherlock'', the followup to Creator/MelbourneHouse's already infamously-buggy ''[[VideoGame/TheHobbit1982 Hobbit]]'', was less a game and more a collection of [[http://www.filfre.net/2013/12/sherlock/ wonderful errors]] strung together with plot. Contemporary videogame magazines had a cottage industry of finding the best bugs.
** Inspector Lestrade plays the game and interacts with [=NPCs=] and game systems in the exact same way the player does. Preventing him arresting the wrong person can be difficult.. unless you wait for him to get in a hansom cab, then tell the driver of ''his'' cab to go somewhere. The cab driver obligingly whisks Lestrade off to your choice of destination, and Lestrade freezes because he doesn't know what to do there.
** By repeatedly giving instructions to the [=NPCs=] it is possible to coax a hansom cab driver out of their cab and onto a ''train'', which then departs. Having done that, returning to the abandoned hansom cab will have you driven to a bizarre location where you can pick up objects such as "innocent, guilty, an opium den, and a Russian agent".
* And ''Demoniak'', a rather obscure text adventure on 16-bit systems, used a similar system to ''Sherlock'' but allowed players to take control of almost any character in the game, which allowed even more creative chaos. For example, one of the normal playable characters is Flame, a superheroine who can transform herself into fire with the command BURN. Rather dourly, giving the command BURN as any other character causes them to spontaneously combust, actually being set on fire and burning to death. As a result, BECOME ing any character who is in your way and having them BURN becomes an excellent way to get past things.
-->Furiously burning Cortex, furiously burning Sondra, and the furiously burning governor are here. The furiously burning governor is burning furiously. The furiously burning governor is dead.
* ''The Meteor, the Stone and a Long Glass of Sherbet'' opens with the player and Lady Amilia riding in a howdah on an elephant's back. It's possible to ask Amilia to pass you objects -- but she will happily give you ''any'' object you can refer to, even ones normally out of reach. She will readily give you herself, for example, meaning she's available to do the same scenes; or hand you the green glow you see in the sky.

[[folder:Card Battle Games]]
* In ''VideoGame/YuGiOhGXSpiritCaller'', the pack glitch. Apparently, whoever was responsible for the code for buying packs en masse did a horrible job of it; there's a fairly easy way to buy all or all but one of the packs in a set for the price of a single pack. This can potentially mean that you're buying 51 packs for the price of one.
* ''Yu-Gi-Oh! GX: Duel Academy'':
** It was possible to give the Copycat monster an obscene amount of Attack points. At least one AI duelist (in this case, Blair) uses Scapegoat, which creates a group of tokens on the field. Bringing out Copycat and having it copy one of those tokens would, strangely, give it more than ''30,000'' points when it came time to attack. Note, however, that the exact circumstances that lead to the Attack increase are not known, so use with caution.
** Burst Stream of Destruction should only be playable if you have a Blue Eyes White Dragon on the field, but the game doesn't check for it, so you got a unrestricted card (i.e. you can have 3 of them) that can destroy all monsters on the enemy field and is also fairly easy to get.

[[folder:Light Gun Game]]
* ''VideoGame/GHOSTSquad'' will still award the "EXCELLENT!" point bonus for Lacard Zimone, the Mission 2 boss, if you fire before his third shot ''even if you miss''.

* Early versions of ''Pinball/GameOfThrones'' has the Martell Super Jackpot Glitch: By choosing House Martell at the beginning of a game (or House Greyjoy after clearing the Martel mission, as House Greyjoy [[AllYourPowersCombined takes on the abilities of every House cleared]]), you can press the button at the front of the machine to add another ball onto any multiball. If this is done the first instant only one ball remains and Super Jackpot is lit, however, Super Jackpot will remain active for the rest of the ball. Any hit onto the battering ram target will award a Super Jackpot, worth a large amount of points. Ordinarily, collecting the Super Jackpot will disable it until you re-do the process all over again to activate another Super Jackpot.
* An as-of-yet unreplicatable glitch in ''Pinball/WHODunnit'' causes the elevator doors to remain open for the rest of the game. Not only does this allow easy access to modes available only on certain floors, but the shot into the elevator is by far the easiest and safest shot in the game. The discovery of this glitch in 2015, twenty years after the machine's debut, got it banned from all high-level tournaments due to its exploitability once activated.
* Because ''Pinball/StarTrekTheNextGeneration'' contains six pinballs loaded underneath the playfield in varying locations to help keep the game constantly moving, this machine is quite prone to accidentally releasing more balls than it's supposed to, providing the player with a sudden multiball (albeit one without any extra effects and one the machine doesn't even realize it's doing). It's exciting for anyone playing, but for advanced players, having more than one ball out at a time also makes for good insurance in case they make a mistake, as ''Star Trek: The Next Generation'' won't penalize the player until every ball has drained. Similar glitches can be done with any machine with a faulty sensor at the plunger, however: If a ball is at the plunger and the machine doesn't detect it, it will load another, letting you play with 2 balls instead of 1. Whether the game considers it the end of the ball when one of them drains, however, depends on the machine and what made the added ball come out.
* If the player reaches the 255th mansion room in ''Pinball/TheAddamsFamily'', any subsequent mansion rooms will provide huge point awards, as the 255th room is the limit of the game's programming (8 bit variable) and it starts glitching up after that. Normally, 9 million is as high as direct point awards go for reaching mansion rooms--these glitched rooms award points in the '''billions'''. That being said, this is a glitch very few people will ever see due to the absurd level of skill required: Even top-ranked players are unlikely to reach 50 rooms.
* In ''Pinball/TalesOfTheArabianNights'', a glitch allows, under some circumstances, for Harem Multiball and Genie Hurry-Up to occur at the same time. Both of them are high-scoring modes that cover each other's downsides: Genie Hurry-Up normally has a strong chance of you losing your ball down the middle, which is negated by Harem Multi-Ball's ball saver (and the fact that there's more than one ball, meaning there's no harm done in losing one or two); whereas a successful shot in Genie Hurry-Up temporarily traps a ball on a magnet, slowing the pace of Harem Multiball to a more controllable state. Under normal circumstances, neither of these modes allow for the other one to begin as long as they're active.
* While playing ''24'', certain conditions cause the Nuke Jackpot to be worth 20 times more points than normal. Considering the normal Nuke Jackpot is the biggest single award until the WizardMode, attaining this bugged Nuke Jackpot pretty much guarantees you beat anyone who doesn't also get a bugged Nuke Jackpot.
* In ''Pinball/JohnnyMnemonic'', getting the Hold Bonus award is supposed to carry your end-of-ball bonus to the next one. Instead, it will award the end-of-ball bonus at the end of your current ball, then award it twice at the end of the next one. This is good news for anyone with any amount of end-of-ball bonuses, but because one mode, Spinner Millions, is worth a ludicrous amount of points and is only given to you during the end-of-ball bonus, this allows you to obtain the points from Spinner Millions three times (or more than that if you can get Hold Bonus again).
* The most recent revision of Star Wars (Stern) has a bug that causes the player to almost never leave Victory Multiball once it is earned, effectively putting the player in a semi-permanent multiball state. What's more is that the major mode that was used to achieve Victory Multiball will continue to run, allowing the player to easily cash in on multi-hundred-million shots far longer than intended. Many players have been able to break 100 ''billion'' without too much effort. Ironically, one of the bullet points of this current revision was to tone down some of the more absurd scoring possibilities...

[[folder:Puzzle Games]]
* ''[[VideoGame/PanelDePon Pokémon Puzzle League]]'' has a habit of freezing either player during a 3D puzzle match. This is one of those cases where the bug is both a GameBreakingBug and a GoodBadBug, as depending on which player is frozen, you'll either have to restart the game or just wait for an easy victory.
* ''VideoGame/{{Tetris}}'':
** In Sega's 1988 arcade version, the UsefulNotes/RandomNumberGenerator uses a very specific seed upon starting up, causing [[http://www.tetrisconcept.net/forum/showpost.html?p=23443&postcount=13 the same permutation of pieces]] to be generated during the first game after a machine startup. This is known as the "power-on pattern", and top-ranking Sega ''Tetris'' players use it to [[{{Cap}} max out their scores]] in the fewest pieces possible.
** ''Tetris DX''[='=]s rotation system is such that your current piece, provided it isn't the square "O" piece, can be kicked back up the wall, over and over, so that the game never actually progresses. If you're astronomically patient or have access to utilities for tool-assisted runs, it's possible to max out the score counter this way through the points earned from fast dropping before you even put down a single block.
* ''VideoGame/{{Scribblenauts}}'':
** The physics engine is decidedly fickle, and known for producing its fair share of bizarre (and hilarious) spazz-outs. Just for starters, objects made with lots of other objects (e.g., sticking together with glue) have a tendency to "creep" along the ground with steady momentum. Sticking too many things onto something Maxwell can pick up (like a BASEBALL BAT) can result in him being flung across the screen when the creation explodes.
** Also, using the "Shrink Ray" on summonable terrain features like the "Hole" creates gaps that it's possible to escape the stage through.
** Terrain features containing water (like the "Sea") can buoy floating objects in themselves without being placed down. This can even be used to carry [[PlotCoupon Starites]] in things such as ice blocks to you!
** Summoning items that always vanish upon being put into the world (like "Bubble") in the level editor results in said item not vanishing, and becoming a lovely fountain of its appropriate particles. If you start the level you've created, they'll stick around, and you can knock them about. Not surprisingly, though, the huge particle streams crash the game rather quickly if you start summoning other things.
** Similar to glue, rope and related objects can create numerous glitches. You can instantly win almost any level by spawning a container next to the starite, attaching a rope to the starite, and then attaching the other end of the rope to the container, which allows you to put the rope and starite inside the container and drag the container all the way to Maxwell instantly.
*** Another rope-related glitch is the classification of attached objects as one object. Basically, if you attach two objects together via rope, they can pass through each other, meaning that you can attach a starite to a gate and then have it fall through to the other side of the gate.
** Attaching an object that causes other objects to gain momentum with one of those items using a rigid body (like glue and planks) yields [[http://www.youtube.com/watch?v=JPQN6V-j2u8 hilarious results]]
*** This includes the "flying bridge" glitch, where using a fishing rod on a bridge Maxwell is standing on causes him to fly to the ceiling or off the screen, where he dies.
** Some animals, like gorillas, can both ride things and be ridden on, allowing you to easily create things like gorilla totem poles that slow the game down to a crawl.
** Scribblenauts Remix has a silly glitch in which making a building ridable can allow the player to walk offstage or even clip through the ground.
* In ''Supaplex'', there are numerous small glitches to avoid getting killed in some occasions and how to manipulate with enemies and explosions. These have found various uses in many of the custom levels.
* ''VideoGame/BlastCorps'' had the Z-Button trick. When in a vehicle, if you are in the right spot next to a building, you could hold the Z-Button down and wait for the [[MostAnnoyingSound doh! sound]] to go away, which was the cue that meant your character got out of the vehicle and, in the process, destroyed whatever building the vehicle was next to at the time.
** Turns out this wasn't a glitch. Instead, it was [[AntiFrustrationFeatures designed as a failsafe]] just in case the player got stuck somewhere that would've otherwise forced them to reset.
* PuzzlePlatformer ''VideoGame/TheCastlesOfDoctorCreep'' had a couple of doors in the castle Doublecross that didn't go where they were supposed to. The effect of these doors was to basically create two shortcuts that considerably shortened the castle.
* Early versions of ''VideoGame/TheWitness'' contained strange glitches where completing specific puzzles under specific conditions would lead to completely unexpected results:
** In the red portion of the swamp (the last portion before activating the laser), solving the puzzle that lowers the yellow cubes in a specific way [[http://i.imgur.com/5mEgqUd.jpg makes disappear]] a large purple cube in a completely unrelated zone of the swamp, even though the purple cube serves only to decorative purposes.
** Early in the game, you can find a locked vault with a puzzle involving hexagonal dots and black and white squares. Much later, in the quarry, you can find a puzzle which is completely identical to the aforementioned puzzle except that it adds an annulation symbol. It's been reported that solving the later puzzle would open the vault even if the former puzzle hadn't been solved yet. However, this is an extremely rare situation, since it's unlikely the vault puzzle hasn't been solved by the time the player is able to reach said quarry puzzle.

[[folder:Rhythm Games]]
* The ''[[VideoGame/DanceDanceRevolution DDR Extreme]]'' arcade cabinet had a difficult-to-time trick in Oni mode. When switching between courses, the song list shuffled off the screen and is replaced by the new one. By pressing the start button in the middle of this animation, the cabinet may accidentally load the correct songs for the course, but load the difficulties from the previous one. Most combinations don't produce anything specialóeither a crash and reboot of the machine or Heavy step charts mislabeled as Challengeóbut a few courses reveal Challenge-difficulty step charts that were DummiedOut and are not playable through any legitimate means.
* Due to the way ''VideoGame/{{DJMAX}} Technika'''s touch screen handles touches, you can do tap notes by dragging your finger across them, and conversely, you can do chain notes by individually tapping each individual segment. Whether this is a legitimate way of playing the game is a matter of debate.
** Normally after completing the first 3 stages of the Heartbeat Set, you'll get [[ThatOneBoss "Colour of Sorrow"]]. However, if you get 75% MAX judgments or less, you'll instead play [[http://www.youtube.com/watch?v=BN9nfiiiXCg "Proposed, Flower, Wolf"]], a beginner-level song. This bug was corrected through an online update...[[BadExportForYou which you don't get if you're playing in a country that doesn't have Platinum Crew support for its Technika machines]].
* ''VideoGame/StepMania 3.9'' (and "3.95", the version used by ''VideoGame/InTheGroove 2'') has a series of bugs that allow for some serious InterfaceScrew. The most famous one is perhaps the "Negative BPM" bug, which can be used to create warps, which can then be used for a wide variety of effects and tricks. It has been leveraged to create crazy fan favorites.
** Unfortunately, this bug was fixed on 4.0. However, sm-ssc ([=StepMania 5=]) turns it into an AscendedGlitch by providing built-in means to perform warps.
* ''VideoGame/RockBand 3'', on [=PS3=] at least: some venues have large props that the rockers sometimes stand on. There's one venue with lots of green lanterns that does not seem to have such a prop, but the game seems to think it does, so rockers will sometimes stand several feet above the stage.
* In ''VideoGame/CryptOfTheNecroDancer''', there is an uncommon bug involved with the tempo switches on the floor. If you set one off, and blow it up before it reverts, the music will ''stay slowed down/sped up'' for the remainder of the level.[[labelnote:*]]Can either be an EasyLevelTrick or a SelfImposedChallenge.[[/labelnote]]
* ''VideoGame/InTheGroove 2''[='=]s [=r21=] update allows players to play custom songs off of their USB drives, but the song must not be tagged as longer than 2 minutes. Emphasis on "tagged"; the game uses the track's metadata to determine if it exceeds 2 minutes, and it's possible to trick the game into playing a "2-minute" song that is actually [[MarathonLevel 5 minutes long]], for example. The [=r23=] update instead cuts off songs at 2 minutes and 15 seconds regardless of metadata.
* ''VideoGame/PumpItUp'' will give out all Perfects for a hold step as long as you keep it held the entire time, even if you hold down the note in advance. A song where this exploit can be put to use is "Pumptris Quattro"'s [=S17=] chart, which is composed entirely of hold notes, allowing a sufficiently-heavy player to sit down on the panels for the duration of the song to obtain [[BreatherLevel the easiest SS ever]].
* Being an early, rap-based RhythmGame, the COOL freestyle system in ''VideoGame/ParappaTheRapper'' is far from perfect & can be easily broken...[[http://www.nicovideo.jp/watch/sm10450253 to hilarious results]].

[[folder:Shoot-Em-Up Games]]
* ''VideoGame/SpaceInvaders'':
** In the original, the "random" point value of the flying saucer was actually a completely predictable function of how many time the player had fired. It was worth 50 points if hit with one of the first 8 shots, 100 points if hit with shots 9 10 11 or 12, 150 points if hit with shots 13 or 14, and 300 points if hit with shot 15; then the cycle started over. A savvy player could count his shots and get 300 points each time.
** A far more overreaching one; when the game was originally designed, the amount of sprites on the screen seriously lagged the system. But by shooting them, and hence removing those sprites from the screen, the system sped up, so the Invaders did too. This mistake, which eventually became an AscendedGlitch, introduced TurnsRed to the industry at large, and while other games like VideoGames/BreakOut did it first, it popularized the entire concept of DifficultyByAcceleration.
* ''{{Sinistar}}'' had a bug that allowed you to acquire 255 ships. It takes a second or two for the Sinistar to eat your ship, during which a Warrior ship can shoot you, making you lose two lives at once. If you started with one life, your number of lives would drop from 1 to 0 to -1. Since this number was stored as an 8-bit unsigned integer, -1 would register as 255.
* ''VideoGame/{{Touhou}}'':
** Later games in the series have Marisa's B firing mode glitched up. In ''Mountain of Faith'' and ''Subterranean Animism,'' using Marisa B with 3-3.95 Power caused insane damage, enough to cut lengthy cards to a third of the length. It's a bit nerfed in SA, though, as you need to shotgun with a specific formation. It also fails in [=MoF=] if the player focuses.
** And akin to this, "Malice Cannon" in ''Imperishable Night''. As the Magician Team (Marisa and Alice), repeatedly tapping the focus button allows both characters' attacks to be used simultaneously. This bug doesn't break the game, but rather moves the ridiculously underpowered Marisa/Alice team closer to the damage output of the other teams.
*** The Malice Cannon actually buffs up the Magic Team to the strongest team in the game, with a ridiculous damage output, although the player still has to deal with the fact that it only fires in front of them. Technically, all four teams have the ability to perform this bug, however, the Malice Cannon is the most notable, because Alice's attack is a narrow laser that reaches across the whole screen in basically the same instant it's deployed, the Malice Cannon can deal consistent damage, instead of waiting for both teammates' bullets to reach the enemy.
** Lunasa from ''Perfect Cherry Blossom'' can glitch at times, making her "Fake Strings 'Pseudo-Stradivarius'" card last unusually little for Reimu A, should you choose to fight Lunasa after the sisters' first joint attack. While the glitch can be observed with a certain degree of consistency during Normal and Lunatic gameplay, it's currently unknown whether or not it can trigger on Hard, given that the script for "Spirit Strings 'Stradivarius'" is noticeably different on this particular difficulty. The glitch, nonetheless, trivializes the card, which comes to ease the heavy-dodging you're normally subject to with Lunasa. [[http://www.youtube.com/watch?v=PTHtus7zoHU you can watch the glitch on action here]] (skip to 5:53).
** In ''Ten Desires'', due to a glitch in the way [[BonusBoss Mamizou]]'s creature bullets are animated, the script that tells the game that a bullet has already been grazed doesn't activate. What this means is that by simply sticking close to any creature bullet, the player can accumulate ridiculous amounts of graze, far more than the actual number of grazed bullets. While all of Mamizou's cards feature this to some extent, it's most noticeable during [[http://www.youtube.com/watch?v=0rncEnJerb4 Wild Deserted Island]], which fills the whole screen with nothing but creature bullets.
** Almost all spellcards in Touhou gradually reduce the points you get for capturing them over time, so capturing a card after 15 seconds gives more of a reward than capturing it after 20 seconds. While this is normal and fine in itself, it can lead to some odd quirks in a few cases; for example, Yuugi's first boss spellcard on Lunatic has a rather low reward for capture. If you spend enough time against the spellcard, the capture bonus will go negative, causing you to actually ''lose'' points for capturing it. Then there's Rorschach in Danmaku, where the point value fails to change at all; if you time it out, the game will consider it a capture, as shown [[http://www.youtube.com/watch?v=hLMOb-NJcpM here]]...though given that this card is ThatOneAttack, scorerunners generally do not appreciate this fact.
** In the later games with spellcard practice (as of this writing, ''Ten Deisres'' and ''Double Dealing Character'') you can practice any spell you've seen with any character. This is intentional. What isn't, though, is that doing this unlocks the relevant ''stage practice'', even if the card in question isn't even in that character's version of the stage.
** Suwako Moriya's first spellcard in the Extra Stage of ''Mountain of Faith'' has a glitch wherein the laser waves that is normally intended to fire downwards will fire on the direction the player was positioned during the pre-boss conversation. The player can cheese the spellcard by positioning himself above the screen on the center before the pre-boss conversation take place. This results with the player only has to dodge the homing bullet bursts without having to contend with the enclosing waves of lasers.
** In ''Subterranean Animism'', Marisa-B's bomb can hit Yuugi, Orin, and Sanae during their pre-midboss cutscenes... before their hitpoints have loaded, instantly defeating them. (there's a reason Marisa B is called "[[FanNickname Marisa Bugged]]")
* In the ''Combat'' game packed in with the original Atari 2600, running your tank into the inside of a corner--usually a corner of the screen--would teleport you to the opposite side.
* In ''Tank Pong'', after one player successfully kills the other and his tank is still in motion during the "death sequence" (i.e. the "dead" opponent spinning), if the victor's moving tank touches the wall bounding the playfield, his tank will suddenly start sliding rapidly along the wall, warping around off the edge of the screen and back out the opposite edge, until the next round begins. If the same victor's tank touches the beaten tank while doing so, he also takes the spinning tank with him in that joyride.
* In any Tank game, having both players' tanks positioned one right in front of the other (i.e. one Tank's gun right on the other's rear) and touching, and having both move forward, will cause both to suddenly begin spinning rapidly in a circle (and passing through any nearby wall or barrier).
* In ''VideoGame/AfterBurner Climax'', after lighting the afterburners for a while they would automatically turn off and your plane would slow down to cruising speed. By deliberately throttling back from the standard middle position and then shoving the throttle forward again periodically, you could maintain afterburner near-continuously. This was not removed from the XBLA and PSN releases.
* In the original ''VideoGame/EscapeVelocity'', one could suppress planetary defense fleets entirely by hiring enough escorts to achieve the {{cap}} on the number of ships in a system.

[[folder:Stealth-Based Games]]
* Franchise/MetalGear series:
** The NES version of the original ''VideoGame/MetalGear'' had a glitch when you entered the computer room, if you went immediately right you would glitch into the final boss room without having to blow up the computer. This was helpful if you didn't rescue the professor (even though you KNEW you needed plastic explosives to destroy the computer, the game won't let you unless the professor told you).
** ''VideoGame/MetalGearSolid'' had the Instant Elevator bug. Rather than wait after calling an elevator, if you hit the button again it would arrive ''instantly''.
*** It also has the Vent Glitch used by speedrunners. Switching to first person view while in a specific position in a specific vent causes Snake to go out of bounds. Guiding him then to certain spot causes a cutscene to be triggered that advances the story to the part where [[spoiler: Snake has been captured]], allowing him to skip 5 bosses, at the cost of having a shorter lifebar.
*** There is also [[https://www.youtube.com/watch?v=YBQShydrjmo&feature=youtu.be this rather difficult to explain glitch]] that allows you to get up close and personal to Sniper Wolf in ''both'' battles. Normally if you try to get too close you are automatically hit by a scripted unavoidable attack that blocks your progress but through a specific glitch involving a grenade and a ration you can render yourself immune to it, run right up, and punch her to death as she [[AIBreaker helplessly strafes around still trying to snipe you]].
** In ''VideoGame/MetalGearSolid4'', Snake reloads the long barrel / scope Desert Eagle with a magazine. However, a glitch means the magazine is inside ''another'' long barrel / scope Desert Eagle, which he duly inserts into the space occupied by the first. It helps if you exclaim "my deagle needs more deagle!" while doing this.

[[folder:Third Person Shooter Games]]
* ''VideoGame/ResidentEvil4'' had several that were BoringButPractical such as running at 1.5 times his normal speed by switching to the [[ShotgunsAreJustBetter Striker]], raising it and then quickly equipping another weapon before the laser sight could activate ([[http://speeddemosarchive.com/ResidentEvil4.html useful but cautiously used]] in [[SpeedRun speedrunning]]). However, the most memorable is Ashley's abilty to [[TookALevelInBadass suplex enemies]] by [[http://www.youtube.com/watch?v=d0Tg1btDrMA whacking them with a door]]. It's also possible to open locked doors from the wrong side with the TMP equipped to bypass entire "find the key" [[FetchQuest Fetch Quests]], pressing L + R before every PressXToNotDie moment which (most of the time) makes the other button prompt appear, and being able to push Ashley through the scenery by getting her into a corner and pushing against her when she ducks (useful for keeping enemies off of her). Also, the gimmick where Ashley scolds you for looking up her skirt is literally set to trigger ''anytime'' Leon's eyes aim up in that direction: even when he's been knocked down by an enemy or his [[CrowningMomentOfFunny severed head rolls between her legs]].
** ''VideoGame/ResidentEvil5'' had a glitch where you could load guns using the inventory... even if they were the gun you had out. In multiplayer, this allowed skilled players to reload near instantly, circumventing the weakness of many weapons and making chaining combos together a lot easier.
* ''Franchise/SaintsRow'' series:
** ''Videogame/SaintsRow2'' has a slight glitch having to do with reloading. Usually, your nameless protagonist will reload dual [=SMGs=] by spinning them in his/her hands and keeping them at his sides. Sometimes holding down the button makes the game act as if you are still firing while you are still in a reloading animation. Meaning it looks like the guy you took out in front of you was killed by some crazy richochet.
** Go at a high speed and ram a gas station pump. You'll blast off farther than the [[Franchise/{{Pokemon}} Team Rocket]] trio.
** ''VideoGame/SaintsRowTheThird'' has a bug where, on occasion, the [=D4TH=] Blossom SMG just fires from its total ammunition without the Boss having to bother with replacing magazines - normally this requires spending a ludicrous amount of money on upgrades.
* ''Mafia'' has several. For instance, while the civilian population's driving AI usually works fine, it sometimes fails amusingly, leading to 'drunk drivers' barely managing to stay on the road and eventually crashing into obstacles. Also, try getting out of e.g. a racing car and stealing a car from gangsters. They will in turn get into your abandoned car, pursue you with it, and die horribly as their AI can't cope with a car that fast.
** Another incredibly useful exploit: Reload your weapon and immediately perform a sideways roll to have your weapon be instantly-reloaded without having to wait for the reload animation to complete.
*** Amusingly enough, ''VideoGame/GrandTheftAutoIV'' has this very same glitch.
*** And ''VideoGame/ResidentEvil4''. Unfortunately you could only dodge when you're being attacked, and most enemies don't give you enough of a warning to use this bug reliably.
* ''VideoGame/GearsOfWar''[='=]s final boss General RAAM is extremely difficult for two reasons, his handheld minigun and his shield of [[GoddamnedBats kryll bats]]. Mercifully, it is possible to trick him into standing behind the last cement block to the right of the platform where he appears, where he stops moving and does not target you with his gun as long as you don't stick your head up from cover. Getting him into this glitch spot is tricky and the other sources of damage can still get you on insane level, but this trick is enough to bring down an impossible fight to an almost manageable one.
* ''VideoGame/{{Oni}}'' has a fair few bugs, both good and bad. A lot of the bad ones (such as enemy {{Mook}}s' inability to sprint or dodge weapons fire) are fixed in the fan-made ''[[http://wiki.oni2.net/Anniversary_Edition Oni: Anniversary Edition]]''. They left in the bug that resets the rate of fire setting on weapons when dropped. Feel like [[NoKillLikeOverkill annihilating someone]] with [[MoreDakka four clusterbomb shots in under two seconds?]] M1-E-Q-M1-E-Q-M1-E-Q-M1. Done and done.
* ''VideoGame/KidIcarusUprising'' has the infamous Play Dead+Jump glide combo. Basically, one of the powers you can equip is Play Dead, which, when used, causes your death animation to play (A Smash Brothers style explosion and a gravestone popping out where you were). The intended use doesn't really work because the actual death animation also involves being knocked back several feet into the air and the gravestone lasting for more than just a second. It also doesn't work as well as a get away tactic because your invisibility goes away almost immediately once you start moving around. It's used more for the fact that you are invisible AND invincible when you use it, making it great for sniping since you won't be moving around much anyway. The bug comes when used with Jump Glide: That power launches you into the air and lets you control your trajectory as you slowly descend. The game doesn't count this as moving and as a result, doesn't de-activate the invincible "dead" state, letting you use the power for more than just sniping weapons, and even with sniping weapons it allows you to change your position, especially useful if someone saw you play dead and was sticking around to destroy you once you "respawn".
* ''VideoGame/{{Splatoon}}'' had a glitch on the Piranha Pit map where, due to object placement in some modes, you could bend your Inkling's neck beyond any sane angle. This happened because the game had no code specifically to handle Inkling posture when attempting to enter a niche shorter than they are tall (which could only happen on that map).
* ''VideoGame/Splatoon2'', meanwhile, once had a useful glitch in Hero Mode where you could re-collect [[ExperienceBooster XP- and cash-boosting]] meal tickets redeemable at the Crust Bucket food truck. They'd still show up grey and nominally give you one Power Egg, but at said truck you could find extra tickets in your collection. Players would exploit this mechanic to grab as many tickets as possible and make grinding easier. However, it got patched out in version 1.1.2; players will now have to unlock all upgrades and then spend an additional 1500 Power Eggs for a random meal ticket instead.

* There was an online Martian Rover Sim in 3D, which had been designed as part of the mission's publicity. The Sim was designed to show how the rover would move and collect samples. It also had some speed settings which, instead of speeding up the whole simulation, increased the speed of the rover, allowing some really stupid stunts. You could take the rover to the edge of the map, where there was a small wall, climb it, and head out into the wide red yonder, which caused the rover to drive upside down through the air, among other things... Not bad for an educational resource!
* Microsoft Sam has a very interesting way of saying [[http://www.youtube.com/watch?v=3B0joNsmWUQ "soi" and "soy"]]. This sound has come to be referred to by some as the [[FanNickname ROFLcopter]].
** The bug with "soi" appears to be that it's pronouncing it as if it were a French word (which it is), so it comes out "swa", but what it's doing with "soy" is just bizarre.
* In the Website/{{Google}} Earth flight simulator, if you hit the ground, you die. However, if you start on the ground, don't take off and be very careful with the controls, the game doesn't register you hitting the ground and dying. Because of this, you can, among other things, taxi a propeller plane through/out of/into the Grand Canyon/Mount Everest and taxi an F-16 on or even under water.
* The [[DevelopmentHell still-alpha]] Windows-clone [=ReactOS=] got a bug in its hard disk driver that caused it not to register and prevent access to disks - or it would have, had the Plug-n-Play infrastructure not been so screwed up that it set everything up anyway.
* ''TabletopGame/MagicTheGathering'':
** The stack operates in a "Last In, First Out" manner. This means that the last ability put into the stack, played in response to something, occurs first. This can be exploited whenever something has a "leaves play" effect and some other effect. Often, these "leaves play" effects undo the previous effect, but if you somehow remove the card from play in response to its other effect, the card will leave play without undoing anything, and then the initial effect activates and never gets undone. This can remove lands, creatures, cards from a player's hand, and life permanently. If you remove the exploitable card from play by returning it to your hand, you can even repeat the effect!
** "Patched" with recent versions of those same cards that are worded so that that trick doesn't work anymore[[note]]The new cards set up a static ability with a duration rather than a delayed trigger. If the end of the duration happens before the beginning, i.e. the card leaves play before exiling the other, the effect never occurs[[/note]]. This has the effect of making formats which only use the 'fixed' versions of these cards much less dependent on exploiting weird rules interactions, but can be pretty confusing when playing older formats (including Modern) where it's also legal to play the older cards with very slightly different wording which does allow for silly stack trickery.
* Website/DeviantART had a bug that if you checked a message as soon as you received it, the time would sometimes say, "In the future."
** The explanation may be more mundane. A lot of web frameworks have reusable functions to convert dates into human-readable relative descriptions, such as "5 minutes ago" or "1 day ago". They're written to be usable for any date in the past or the future: so, for example, you could have reminders that activated "in 2 days" or "in 30 minutes".
* Certain more recent ''VideoGame/{{Tamagotchi}}'' models have [[http://www.pixelmood.com/tamagotchi_connection_debugging.htm a trick]] with a pencil and a screwdriver that lets you access the device's debug menu, which allows you to choose any pet you want, including those that were DummiedOut.
* Website/YouTube:
** [=YouTube=] had a bug where if you put a 0.1 second pause at the end of a video, it will sometimes loop back to the start. This led to some interesting results. Sadly it doesn't work anymore.
** The official iPhone and Android apps for the site both have exploits that allow you to view 18+ videos without an account. They also have exploits that allowed private videos to be viewed by anyone, such as when ''VideoGame/TeamFortress2'''s "Meet the Spy" video was leaked a few hours earlier than its intended release.
** [=YouTube=] has a [[BlindIdiotTranslation hilariously]] [[TranslationTrainwreck broken]] auto-caption transcribing system that never fails to completely mangle whatever you ask it to add subtitles to. Most of the problem seems to come from the fact that the system tries to translate ''[[LiteralMinded every sound]]'' it hears into dialogue, which then becomes a complete mess. It has provided numerous hilarious captions and even one case of AscendedFanon in the ''WesternAnimation/MyLittlePonyFriendshipIsMagic'' series. [[note]]A one off-character was named "Steven Magnet the Sea Serpent" in a toy line after the fandom gave the name to the as-yet unnamed character thanks to one of these translation screw-ups.[[/note]]
* Some forums have bugs where a person's post can be shunted a few minutes (or even hours) back or forwards in time and end up appearing in the wrong place. [[http://www.ditl.org/forum/viewtopic.php?p=256649#p256649 While this can be amusing enough as it is]] it is even better when [[http://www.achrongame.com/forums/viewtopic.php?f=11&t=539 it's a forum about a time travel game]].
** Similarly, for Pi Day one Website/{{Wikipedia}} admin tried to block another for 3.14159265359 seconds as a joke, [[https://en.wikipedia.org/wiki/Wikipedia:Village_stocks#SQL_for_the_Time-traveling_Block_Breaker_award but somehow ended up setting the block to expire in 1975, which the person on the receiving end of the block saw as expiring in 2021.]]
* ''Series/FamilyFeud'' on the SNES was very buggy in terms of what it would accept as the correct answer. The game usually just checks if the first few letters of your answer matches any answer on the board or if they're in the same order regardless of what other letters are between them, so sometimes entering gibberish, swear words, or just about anything else could match something on the board even if your typed response is way off the mark. Milked for all it's worth in [[http://www.youtube.com/watch?v=k5tyMXXDPX4 this TAS]], and discovered hilariously in this WebVideo/GameGrumps [[http://www.youtube.com/watch?v=uN9x1Akc0hYclip clip.]]
* In ''VideoGame/GrandTheftAuto'', pressing the horn button while on foot would make the player character fart and belch. This action can still be done if the player is killed.
* Someone on Website/{{Facebook}} discovered the Thai ideogram ส็็็็็็็็็็็็็็็็็็็็็็็็็ does a neat format-breaking trick, so it [[MemeticMutation spread quickly]].
* Similarly, someone realized that you could abuse combining marks in Unicode to make characters stack and overlap. Th̢i̢s ̢uńlea͞s̨he͏d̛ t̕he ͞ni̡ghtma͟ri͡s҉h́ '''WebOriginal/{{Zalgo}}''' ùpon̕ t̕he w̶o҉r͏l̢d.̀ H̵̕͜͟͝e̢҉ ̛͏̴̕c͘͢ò́͜͢͞m҉̢̛́é̸͟͝s͡.̵͢͞҉͢.̵̀͘.̵̀͢͞͞
* In ''TabletopGame/VampireTheRequiem'', there's an ''in-universe'' Good Bad Bug with the third tier of the Coil of Blood (which causes a vampire to receive three points of Vitae for every two Vitae they actually drink). The bug is when two vampires who know it use it on each other, allowing them to harvest theoretically infinite amounts of Vitae. It's well-known and generally banned due to the almost inevitable consequences of the ensuing [[LoveMakesYouCrazy Vinculum]].
* One online ''VideoGame/{{Pokemon}}'' battle simulator will sometimes get stuck on processing a move in a battle against an NPC, forcing the player to refresh the screen and turning back the clock to the last action taken by the player. Very helpful if the last thing the NPC did was knock your Pokémon out.
* In-story example: ''Disney/WreckItRalph'' features ''Sugar Rush'', featuring Vanellope von Schweetz as a "glitch". She's barred from appearing in the game for fear that her presence will cause their game to be decommissioned. When she finally appears, she's the most popular character as players exploit her quasi-random teleportation to get an edge in races.
* In-story example: ''Literature/SnowCrash'' describes a bug in the Metaverse which Hiro exploits to move through walls.
* In the Music/{{Vocaloid}} song [[https://www.youtube.com/watch?v=XyHbuWANAUA Light]], Mikuo is only a bug from Miku's data, however he didn't do any harm to the computer, instead he is described as an entity who born from Miku's wish to not be lonely, and he is aware that he is just a bug, a false existence, and will be soon deleted. Cue the TearJerker moment when he finally got deleted by Miku's "master".
* In the UsefulNotes/TRS80 game ''VideoGame/{{Starfighter}}'', pressing a number key 0-7 accelerates you to a pre-selected speed of 2^(number) - 1. Thus, pressing 3 accelerates you to speed 7, pressing 4 accelerates you to speed 15, etc.. It didn't take the players long to discover that if you pressed two number keys at the same time, you'd accelerate to an intermediate velocity -- and that holding down all the number keys 0 through 7 at the same time would accelerate you to speed 254, faster than any spacecraft you'd ever encounter.
* ''TabletopGame/{{Warhammer 40000}}'':
** "A [[ThePoliticalOfficer Commissar]] (of any rank) will [[ObviousRulePatch never execute himself]]."
** "Please note that it is ''not'' possible to [[Film/MontyPythonAndTheHolyGrail master-craft grenades]]!"
** "Under no circumstances can any [Necron] make more than one teleport move in a single turn. There are no exceptions to this, [[TakeThatAudience no matter how clever your logic]]."
** In Games Workshop's ''Literature/TheLordOfTheRings'' tabletop game had a rule that stated "Frodo counts as a banner in all respects". A later reprint of the rulebook added "with the exception that he cannot be picked up and wielded by another model". [[GrievousHarmWithABody Oh, the mental images]].
* In ''Series/BarRescue'', one of the bars that the show went to somehow managed to drop a grilled cheese sandwich into a fryer. The resulting fried grilled cheese sandwich was enjoyed by the host of the show and the staff of the bar, who then put it on the menu.
* A good amount of games that has developed these GoodBadBugs, have gotten good to the point that they are seen as part of the game, sometimes becoming an AscendedGlitch. Some of those bugs go from Wall-Bouncing from GearsOfWar, to canceling the reload animation in some games, and crouch-jumping. Some of these have become so well integrated with the game that they are seen as part of the game and sometimes crucial, to the point that they are allowed at tournaments and official games.
* The robot used for Google Street View images was programmed to recognize human faces and [[{{Main/Pixellation}} blur them out]] for the sake of privacy. Amusingly, it sometimes can't tell actual faces from representations of them, so it will blur the faces of [[http://thecreatorsproject.vice.com/blog/the-anonymous-gods-of-google-street-view religious monuments, mascots, and other large statues]].
* {{UsefulNotes/Steam}} sometimes messes up the prices of games during sales, resulting in the ''VideoGame/NarutoUltimateNinjaStorm'' games being on sale for $5.61...with its original price being erroneously listed as ''[[https://pbs.twimg.com/media/COjtVf7UwAAVilE.png 184 quadrillion dollars]]''. Though being part of a LongRunner AnimeAndManga franchise, [[CrackIsCheaper it probably feels like it costs that much]].
** When ''VideoGame/CrimzonCloverWorldIgnition'' debuted on Steam, a discounting error resulted in the deluxe pack (which includes the game and also the soundtrack) [[http://i.imgur.com/jajvnGG.png costing less than the game itself]]. This was fixed less than an hour later.
* ''Webcomic/TheOrderOfTheStick'' invoked this in a battle with the Linear Guild. Cleric Durkon opened up with a spell that whammied anyone evil-aligned in the vicinity, which came in handy when the villainous Nale used tried to use CharmPerson on TokenEvilTeammate Belkar. To quote Roy: "It's not a bug, it's a feature."
* My Handy Design, a third party Amazon vendor, used an A.I. to determine popular image searches, print them on [=iPhone=] cases, and sell them online. Something went wrong with the algorithm they used, and the end result was [[http://www.boredpanda.com/funny-amazon-ai-designed-phone-cases-fail/?utm_source=facebook&utm_medium=cpc&utm_campaign=AwkwardFamily thousands of unlikely phone case designs]] with overly specific listings like "Adult Diaper Worn By An Old Man With A Crutch Cell Phone Cover Case [=iPhone=] 6".

[[folder:Real Life Examples]]
* The 1981 Cadillac El Dorado had a balancing problem which was corrected by installing a steel plate underneath the driver's seat. This saved Frank Lawrence "Lefty" Rosenthal from a car bomb attempt, which served as the inspiration for a scene in ''Film/{{Casino}}''.
* Electronic novelty items that speak or sing while moving a part of them, such as singing fish. The fact that a fish on a plaque is flapping its tail to the music and lipsyncing is funny enough as it is to many people, but let the batteries get low and they get slowed and off-keyed when they try to move themselves. The effect can be [[http://www.youtube.com/watch?v=G3YKda3gaSY pretty funny]] or NightmareFuel depending on your sense of humor.
** Some synthesizers, like the [[http://www.youtube.com/watch?v=tsKXJdGnxhc Hing Hon EK-001]], can sound like they're dying if they're low on batteries, too.
** This happens with the old edutainment toy Speak n' Spell, but that's a [[NightmareFuel Bad Bad Bug]].
** The [[http://en.wikipedia.org/wiki/Simon_(game) Simon]] memory game would actually run faster (and its notes would play higher) if the batteries started to get weak, making for a more difficult challenge. However when the batteries were really weak, the device would no longer work properly and would simply become a light show.
** Many [[https://en.wikipedia.org/wiki/Watch#Talking_Watches talking watches]] and [[https://en.wikipedia.org/wiki/Talking_clock#Assisting_the_blind clocks]] do this when battery power is scarce.
** Averted by many modern toys- these toys now have circuits to detect when their batteries are low and cut themselves off completely instead of soldiering on and scaring the kids.
* Genetic mutations. They may produce traits that hinder an individual's chance of survival, or an extremely adaptive trait or a whole new species, and sometimes both at once. Or even traits that do nothing at all, such as eye color.
** Sickle cell disease is not a very pleasant condition to have, being a defect in the gene for oxygen-carrying hemoglobin that results in misshapen red blood cells. These sickle cells are less capable of transporting oxygen and prone to getting painfully stuck in the patient's blood vessels. However, being a ''carrier'' for sickle cell (having only one copy of the recessive mutation) makes you resistant to the malaria parasite, which is by far the likeliest explanation for why sickle cell trait hasn't been selected out; regions where malarial mosquitoes are endemic, and regions where the sickle cell trait persists, are largely coterminous.
* The Cowpox virus. Being affected by this benign disease makes one immune to the far deadlier smallpox. This observation and subsequent successful use of a preventive treatment against smallpox inspired the development of vaccination.
* Will Keith Kellogg and his brother, John Harvey Kellogg, of Battle Creek Michigan, were Seventh-Day Adventists and ran the Battle Creek Sanitarium in the late 19th century; the food, in accordance with their beliefs, was to be served bland. One day, they had to leave some wheatmeal sitting to take care of a problem at the Sanitarium and came back to find it went stale. Since they had to keep a tight budget, they couldn't just throw it away, so they decided to roll the stale wheatmeal to make long sheets of dough. They were, however, surprised when the wheatmeal instead broke off into flakes, which they baked and served to the patients. It turned out to be very popular breakfast food with the patients, so they decided to play around with the recipe by substituting other grains for wheat. They struck gold with cornmeal and went into the breakfast cereal business, [[AndNowYouKnowTheRestOfTheStory and the rest, as they say, is history]].
* The Winchester 1897's external hammer meant it lacked a trigger disconnector, which was never considered a problem as the gun operated as intended. However, this meant that you could fire the shotgun simply by holding the trigger down and pumping the action, a phenomenon known as "slam firing". This essentially meant that [[MoreDakka its rate of fire depended on how fast you could pump]]. Dangerous at a shooting range, lifesaving in the trench warfare of UsefulNotes/WorldWarI. At least, [[MookHorrorShow if you weren't on the receiving end]].
** This was such a horrific thing to be on the receiving end of that Germany actually accused the United States of human rights violations for using the shotguns to clear trenches, citing the part of the Geneva Convention restricting the use of cruel and unnecessarily painful weapons. Note that, in the trenches, your one other option was a trench knife that would undoubtedly cause a [[FateWorseThanDeath festering wound in a war zone.]] Compared to that, [[MercyKill the shotgun was downright humane.]]
* Quantum tunnelling. There's a finite probability that something thought impossible in classical physics, like an electron moving through an insulator, can happen. It's because of this that flash memory and electron microscopes work. And the Sun keeps shining for that matter.
* The TRS-80 color computer, back in the 1980s, had a glitch where the computer did not know if it had already written color to a pixel. This flaw allowed a far greater color pallete because multiple color instructions could be written to the same pixel, which then displayed much the same as blending colors on an artist's pallete.
** The fact that the NTSC color signal causes artifacting as a whole. Computer programmers were initially frustrated that it made text borderline unreadable at 80 columns with some color combinations due to the burst overlap causing blurring to the text, which doesn't happen on RGB monitors. However, they soon discovered that by carefully placing their pixels and choosing their colors, they could create colors that were never in the computer's palette to begin with. And the kicker is, this bug is a fault with the way NTSC signal works, meaning it was exploited by every single computer system with a color limitation but output to TV- documentations show that the trick has been used on the UsefulNotes/AppleII, UsefulNotes/Atari8BitComputers, UsefulNotes/{{Commodore 64}} and even [[UsefulNotes/IBMPersonalComputer PCs]].
* Gary Gygax bought a bag of cheap plastic toy dinosaurs to use as miniatures in the new fantasy-based tabletop war game he and his friends were messing around with. Several were so badly-crafted that they not only didn't look like dinosaurs, but they didn't look like anything that could possibly exist in the real world. Rather than throw them out, Gygax made up names and abilities for the glitch-marred toys, ultimately adding three iconic monsters -- the bulette, owlbear, and rust monster -- to the ''TabletopGame/DungeonsAndDragons'' game.
* According to the founder of musical instrument maker Roland, the TR-808 drum machine was built with a large consignment of defective transistors between 1980 and 1983, which contributed to the machine's distinctive sizzle sound. Since then, attempts to replicate the sound have proven unsuccessful due to the fact that modern transistors are too perfect.
* The Keurig 1.0 allowed a user to dispense plain hot water for tea bags, noodles or whatever you needed hot water for by doing all the steps to make a beverage with a k-cup, just by not inserting the k-cup into the receptacle. The Keurig 2.0 now [[AscendedGlitch has that as a standard option,]] asking you if you want to simply dispense hot water if you don't insert a k-cup after closing the receptacle.
* In the '50s and early '60s, electric guitarists strove to eliminate feedback and distortion in favor of a clean sound. The emergence of heavy rock in the mid-late '60s prompted guitarists like [[Music/TheWho Pete Townshend]] and Music/JimiHendrix to exploit feedback and distortion for ever-louder sounds and changed rock and roll forever.
* A key part of the Mellotron's (a tape-based forerunner of the modern sampling keyboard) distinctive sound is that all of the recordings of an instrument were made in isolation from each other, resulting in some very powerful string sounds.