A professionally-published story that evolved from FanFic. This can overlap with SerialNumbersFiledOff, but it [[TropesAreNotBad is by no means necessary]]. The setting of the new work will often be suspiciously similar to the source material for obvious reasons, but the plots of the two stories can come out very different indeed. Alternatively, a number of these began as {{Transplanted Character Fic}}s, which are easier to publish professionally as the only connections to the original canon are character personalities and inter-relationships that are too vague to be covered by copyright. A PromotedFanboy might even rework his fanfic as an official part of the franchise.

On occasion, a fanfic becomes its own legitimate franchise without bothering to cut all its ties to the original, complete with its own fanbase outside fans of the original, with the blessing of the original work's copyright owners. In some cases, some fans may not even realize that it was a derivative work.

In other media, this can applied to video games that originated as unofficial fan games or {{Game Mod}}s.

Compare the WeirdAlEffect, where fans of a derivative work forget the original existed. Also compare SpiritualAdaptation, where a work does not violate copyright law, but fans consider it to also be similar to the source material. See also HumbleBeginnings, of which this can be considered a subtrope.

Contrast AscendedMeme and AscendedFanon, where derivative material is later incorporated into the canon material, and the similar RunningTheAsylum, where fans gradually take control of the original franchise as time goes on and start publishing [[{{Canon}} official material]] that looks like fan fiction. See also SerialNumbersFiledOff and CaptainErsatz.

[[folder:Anime & Manga]]
* ''Manga/NyoronChuruyaSan'' started from a {{doujinshi}}.
* The ''Roleplay/RecordOfLodossWar'' franchise began with edited accounts of a ''TabletopGame/DungeonsAndDragons'' campaign, quickly becoming popular enough to spawn its own [[RecursiveAdaptation game system]], novels, manga, multiple {{OVA}}s, and a television anime.

[[folder:Audio Play]]
* The Japanese drama CD ''Yours for an Hour'' surprisingly started out as a ''western'' slash fanfic of ''Manga/{{Naruto}}''. It went as far as using Creator/JunkoTakeuchi and Creator/NoriakiSugiyama for the leads.
* The founders of ''AudioPlay/BigFinishDoctorWho'' were part of the ''AudioPlay/DoctorWhoAudioVisuals'' fanwork community, and five Audio Visual plays were remade by Big Finish, with another getting a StealthSequel.

[[folder:Comic Books]]
* Creator/GregRucka's espionage series ''ComicBook/QueenAndCountry'' is an acknowledged ascended fanfic of the British TV series ''Series/TheSandbaggers''.

[[folder:Film - Live Action]]
* Creator/GuillermoDelToro stated in an interview that ''Film/TheShapeOfWater'' began life as some doodles he made after seeing ''Film/CreatureFromTheBlackLagoon'' as a child, when he wondered "why couldn't the fish monster and his beloved be happy together?". And so, many years later, came an Oscar-winning film.

* YoungAdult author Creator/CassandraClare started off as a [[Fanfic/TheDracoTrilogy fanfic author]] and later used lines from her own fanfics in her original work.
* ''Series/DoctorWho'' and Franchise/DoctorWhoExpandedUniverse examples:
** The fourth Literature/DoctorWhoNewAdventures novel, ''Timewyrm: Revelation'', with the Seventh Doctor and Ace, came out of a Fifth Doctor and Tegan fanfic published in a fanzine. Creator/PaulCornell expanded and changed quite a bit and made it into his first novel.
** ''The Highest Science'', an early NA by Creator/GarethRoberts originated as a crude fan story. It turned into ''his'' first novel. This, in turn, formed the loose basis for the television story "Planet of the Dead", which he cowrote with Creator/RussellTDavies.
** ''The Left-Handed Hummingbird'' by KateOrman began as a fan fiction for the Australian fanzine Pirate Planet.
* ''The Literature/VorkosiganSaga'', was at a very early conceptual stage ''Franchise/StarTrek'' fanfiction; Beta Colony and Barrayar are reminiscent of the Federation and the Klingon Empire, respectively. Of course, it diverged away and became its own universe almost immediately.
* "Negri's Boys" by Charles Coleman Finlay, which was originally fanfic of Bujold's work, was rewritten with the serial numbers filed off as "The Political Officer". It was published in ''TheMagazineOfFantasyAndScienceFiction'' and nominated for the {{UsefulNotes/Hugo|Award}} and UsefulNotes/NebulaAward.
* Similarly, this is Naomi Novik's origin story for the ''Literature/{{Temeraire}}'' series:
--> "...it was started on January 8, 2004, about ten days before I sat down to write a different fantasy AU story and suddenly went, you know what, this isn't so much FanFic anymore, and these aren't [[Literature/AubreyMaturin Jack and Stephen]], ("[[Music/TalkingHeads this is not my beautiful house]]") and off I went to frolic with dragons."
** Novik's Literature/SherlockHolmes [[http://yuletidetreasure.org/archive/75/commonplaces.html fic]]-[[http://www.amazon.com/gp/product/1597801607/ref=s9_simi_gw_s0_p14_t1?pf_rd_m=ATVPDKIKX0DER&pf_rd_s=center-2&pf_rd_r=1AJS25W8CVGSMNHEZXR9&pf_rd_t=101&pf_rd_p=470938631&pf_rd_i=507846 turned-published-pastiche]], Commonplaces, is another example.
* Creator/HarryTurtledove's ''Literature/{{Videssos}}'' cycle began as Fourth Age ''Literature/TheLordOfTheRings'' fanfic.
* ''Literature/FiftyShadesOfGrey'' used to be a ''Literature/{{Twilight}}'' [[{{Mundanization}} Mundane-AU]] fanfic named ''Master of the Universe''.
* Examples of "pulled to publish" fanfics plague the ''Literature/{{Twilight}}'' fandom: [[http://www.sharetermpapers.com/general-b35/twilight-fanfiction-13292/90/?PHPSESSID=9e62d70df2aa96e733031d7e70f5b498#msg115742 here is the list]].
* ''Devil's Brand'', Casea's Major's thinly-veiled work of ''Fifty Shades'' fanfic, making it an ascended fanfic of an ascended fanfic!
* [=Dennis L. McKiernan=]'s Literature/{{Mithgar}} novels (''The Iron Tower'', ''The Silver Call'', ''Hel's Crucible'') started off as ''Literature/TheLordOfTheRings'' fanfic. Doomsday wanted to publish. Tolkien Estate said "no". Changing the names and filing the numbers off for the "Silver Call" duology required inventing a new backstory of a great war against evil to replace ''The Lord Of The Rings'', and thus the Iron Tower trilogy came about. The rest of the series grew more divergent from there, but the Moria-analogue in those first books is unmistakable.
* ''Series/StarTrekTheOriginalSeries'' examples:
** Some (most?) of the ''Star Trek: The New Voyages'' anthologies came from stories originally published in fanzines.
** The 1983 tie-in novel ''Killing Time'' by Della Van Hise was and still is thought to be originated as SlashFic about Kirk and Spock. The truth is, according to author Della Van Hise, the original printing was from a non-proofed, and therefore "not approved by Paramount" manuscript accidentally sent to the printer. Creator/{{Paramount}} discovered this and [[ExecutiveMeddling ordered the first printing run pulped]][[note]]but didn't get them all; hunting out first-print editions of the novel is a popular hobby for K/S fans at used bookstores[[/note]]. An edited second printing came out shortly thereafter wherein most changes were minor single sentence or word changes designed to reduce the subtext. But this led to unstoppable rumors that an original, explicitly K/S, version of ''Killing Time'' exists. The author says, "There is no such manuscript."
** The Original Series novel ''Literature/{{Ishmael|1985}}'' is a crossover between ''Trek'' and the Western TV show ''Series/HereComeTheBrides'' (1968-1970). (Inspired entirely by the fact that Mark Lenard appeared in both.) [[http://barbara-hambly.livejournal.com/82721.html According to Hambly,]] she dug her original fanfic out of a drawer when she heard Pocket Books was looking for Star Trek authors, and in fact offered to rewrite the setting as a generic Western, but the editor told her it wasn't necessary.
* ''Literature/DivineBloodNovels'' was originally a MegaCrossOver fanfic of several anime (most notably ''Manga/RanmaOneHalf'', ''LightNovel/FullMetalPanic'', and ''Manga/AhMyGoddess'') which eventually developed enough mythos and themes of its own that the author decided to [[SerialNumbersFiledOff file off the serial numbers]] on the characters and make it into its own novel.
* Many lesbian romantic novels of the early 2000s started off as ''Series/XenaWarriorPrincess'' Xena/Gabrielle {{Transplanted Character Fic}}s, known in the ''Xena'' fandom as "uber" fics. Tall, dark-haired, bitter woman meets sweet, good-natured blonde, and romance ensues? It just might be an uber.
** There's also a few uber-Glee lesbian novels starring the equivalents of Quinn and Rachel ("Faberry").
* ''Literature/CaptiveOfTheRedVixen'' started out as an AU fanfic of the webcomic ''Webcomic/{{Terinu}}'' where Melika (renamed Melanie Lovejoy in the final draft) became a pirate.
* ''Literature/DogandSpiderPrivateInvestigations'' was actually originally a short story leadin to a Marvel universe RP campaign. Every player was to write a story as to how their character joined the main campaign. The author, who was going to play Spider-Woman was the only one who wrote anything of note. At the encouragement of the group, he took that short story and turned it into an entire series. Jessica Dombrowski's origin story and dialogue in the first 30 pages or so of book one become more obvious if you know this, though the series diverged heavily thereafter.
* ''Literature/SpectralShadows'' started out actually as a sequel fanfic to Bambi, but when Disney was able to still hold onto the rights of the book and characters ended up crafting their own story out of what they had at that point.
* ''After'' by Anna Todd started out as a Music/OneDirection fanfiction about an OC falling in love with band member Harry Styles.
* The British SF writer Suzanne Palmer published an early short story called "Concession Girl", which was '''blatantly''' a first-season ''Series/BabylonFive'' fanfic with the character names changed and the alien characters made less humanoid. Despite this, any B5 fan will instantly recognise Londo, G'Kar and Garibaldi. The Garibaldi character even retains the initials MG. Cheekily, fandom culture at the time would almost certainly have denounced the story as a MarySue (the original-character female protagonist saves "Londo" and "G'Kar" from a human-chauvinist terrorist attack and ends up dating "Garibaldi").
* ''Literature/ASymphonyOfEternity'' started out as crossover between ''Literature/{{Flashman}}'' and ''Franchise/CodeGeass'' before evolving into a Space Opera that uses magic instead of technology and ramping up the conflict to a Galactic Scale, oh it also has a Deathstar with two energy beams.
* ''The Wayward Astronomer'' by Geoffrey Thomas started off as a fanfic for ''WebComic/{{Dreamkeepers}}'' that became an official Dreamkeepers work.
* ''Morning, Noon & Night'' by Michael Payne started as a ''WesternAnimation/MyLittlePonyFriendshipIsMagic'' fanfic ''Half the Day is Night''. It was heavily rewritten, all the characters changed to non-pony species (unicorns become humans, pegasi become birds, earth ponies become dogs) and published on Amazon.

[[folder:Mythology and Religion]]
* Lancelot of the [[Myth/KingArthur Arthurian legends]] came by way of French storytellers. Percival was an OC. It could even be said that the entire Arthurian Canon is, in its own way, fanfiction.
* OlderThanFeudalism: ''Literature/TheAeneid'', widely hailed as the first work of literature ever and the model for much that came after, was basically a PerspectiveFlip {{fanfic}} continuation of ''Literature/TheIliad''.

[[folder:Tabletop Games]]
* ''TabletopGame/DungeonsAndDragons'' is something of a strange case. The game borrowed heavily from Creator/JRRTolkien (and a few other fantasies, such as Creator/JackVance's ''Literature/DyingEarth'' series, Creator/PoulAnderson's ''Literature/ThreeHeartsAndThreeLions'' and Creator/FritzLeiber's ''Literature/FafhrdAndTheGrayMouser'' series), as well as various more obscure mythologies, but had many unique elements as well. The franchise owners have ended up splitting the game rules into "trademarked material" and "open source material", and encourage others to develop derivative material based on the open source components. In addition, the owners have also licensed derivative settings that have gone on to become book or video game series enjoyed by readers who aren't necessarily fans of the pencil and paper game, including ''TabletopGame/DragonLance'', ''TabletopGame/{{Greyhawk}}'', ''TabletopGame/ForgottenRealms'', ''TabletopGame/{{Planescape}}'', ''TabletopGame/{{Ravenloft}}'' and ''TabletopGame/{{Spelljammer}}''.
** ''Franchise/TheElderScrolls'' setting was originally a home-brew ''Dungeons and Dragons'' module.
** Ditto for ''Literature/MalazanBookOfTheFallen'', which originated as the two creators' home-brew setting.
** ''Literature/RhapsodyOfFire'' based epic storylines of their songs on their D&D campaign.
** ''TabletopGame/ForgottenRealms'' were born as a setting ''before'' voluntarily going under ''TabletopGame/DungeonsAndDragons'', though fleshed out mostly after. Whether basic (''TabletopGame/{{Greyhawk}}'') rules were more of inspiration or problem is up to Ed Greenwood -- he both constantly kicked them aside and used new edition change for the "Time Of Troubles" overhaul.
* ''[[http://en.wikipedia.org/wiki/Renegade_Legion Renegade Legion]]'' was originally set in the ''Franchise/StarWarsExpandedUniverse''.
* ''TabletopGame/AfterTheBomb'' was originally created for ''Franchise/TeenageMutantNinjaTurtles'' 'verse.
* The ''International Super Teams'' setting for ''TabletopGame/{{GURPS}}'' had its genesis in an unused timeline and history written for a ''TabletopGame/VillainsAndVigilantes'' campaign in which [[@/LooneyToons the author]] was a player.
* ''TabletopGame/{{Warhammer 40000}}''
** [[http://1d4chan.org/wiki/The_Guy_Who_Cried_Grendel Castus Grendel]], the [[BadassNormal low-level acolyte]] who tried to [[HeroicSacrifice delay for one round]] a daemon that can eat {{Space Marine}}s for breakfast. Grendel ended up [[SingleStrokeBattle decapitating it in one hit]] with a simple knife purely on a blessing of RandomNumberGod (or maybe the GodEmperor?). Then this hilarity continued to absurd degrees and [[SerialEscalation beyond]]. Started as an amusing session report, ended up mentioned in {{canon}} material (the last link in that article).

[[folder:Video Games]]
* The Nintendo 3DS Version of VideoGame/{{VVVVVV}} includes 18 fanmade levels, and canonizes those levels.
* One of the most prominent examples in all of video gaming: ''VideoGame/MsPacMan'' was originally an unofficial GameMod of ''VideoGame/PacMan'' named "Crazy Otto", which was picked up by Midway and converted into an out-and-out sequel. Although this was originally done without Namco's consent, the character and others inspired by her would later appear in various offical Pac-Man media.
* Save for the ''Videogame/HalfLife'' series, all Creator/ValveSoftware works were developed from fan mods:
** ''VideoGame/TeamFortressClassic'' is an official sequel to a ''VideoGame/{{Quake}}'' mod, which was ported to ''VideoGame/HalfLife1'''s engine. As is ''VideoGame/TeamFortress2'', by extent.
** ''VideoGame/CounterStrike''? It was a ''Half-Life'' mod. So was ''Day of Defeat''.
** And ''VideoGame/Left4Dead'' was originally inspired by a zombie mod for ''Counter-Strike''.
** ''Videogame/{{Portal}}'' was inspired by the student project ''Narbacular Drop'', and the gel mechanic in ''Videogame/{{Portal 2}}'' was developed from ''Tag: The Power of Paint'' (Valve hired ''the entire'' programming team of the latter). Also, the UsefulNotes/{{Xbox 360}} UpdatedReRelease ''Portal: Still Alive'' contained some levels from the mod ''VideoGame/PortalTheFlashVersion [=MapPack=]''.
** ''VideoGame/AlienSwarm'' and ''VideoGame/{{Dota 2}}'' also count, having originally been mods for ''VideoGame/UnrealTournament2004'' and ''VideoGame/WarcraftIII'' respectively.
* Similarly, ''VideoGame/UnrealTournamentIII'' has the Greed mode from the Titan Pack, (or [[UpdatedRerelease UT3 Black]], depending where you obtained the game) which started as a mod for ''Unreal Tournament 2004''. His creator, Mystikal, is now working for Creator/EpicGames.
** The Translocator in ''[[VideoGame/UnrealTournament2004 UT2003]]'' and later has a remote camera within the transport-destination disk. This idea was taken from "Translocam", a mod that added this functionality to the classic Translocator.
* Hours before the ''VideoGame/{{Doom}}'' modification WAD "Evilution" was set to be released, the creators, Team TNT, were emailed by Creator/JohnRomero offering a publishing deal. It ended up as half of ''Final Doom''. This decision, however, resulted in a BrokenBase: many players were thrilled to see a fan production become canon, while others accused Team TNT for "selling out" their fans.
** One of the most common types of mods created for ''Doom 3'' was the kind which removed the necessity to put away your gun when you wanted to use the flashlight. For the ''BFG Edition'', id made the flashlight a part of the player's armor.
* ''VideoGame/RedOrchestra'', ''VideoGame/KillingFloor'' and ''VideoGame/AlienSwarm'' were all originally mods for ''VideoGame/UnrealTournament2004''. The developers of the first founded Tripwire Interactive, who also published the second. The developers of the third were hired by Valve and eventually ported it to the Source engine.
** ''Killing Floor'' also tends to make some well-made custom maps official through patches.
* TowerDefense began as mods for ''VideoGame/StarCraft'' and ''VideoGame/WarcraftIII'' but later became a standalone genre.
* ''VideoGame/FallFromHeavenAgeOfIce'' was included in "[[VideoGame/{{Civilization}} Civilization IV: Beyond The Sword]]."
* ''VideoGame/TroubleInTerroristTown'' started as a simple game mode for ''VideoGame/GarrysMod'', but it went on to win the Fretta contest (a contest to see who could win the best gamemode using the new gamemode framework, called Fretta) and grew in popularity so much it now comes with the game.
* The "Fudge Pack" and "10th Anniversary" releases of ''VideoGame/{{Postal}} 1'' and ''2'' include the ''Eternal Damnation'' and ''A Week in Paradise'' mods for the second game.
* ''Tempest Tubes'' was a popular unofficial hack of ''VideoGame/{{Tempest}}'' that Creator/{{Atari}} ended up distributing officially.
* ''VideoGame/DragonQuestI'' was a VERY thinly-veiled d20 game in the style of ''Dungeons & Dragons''.
** ''VideoGame/FinalFantasyI'' was also heavily inspired by D&D, to the point that they had to edit a few monsters because of copyrights (the [[http://images3.wikia.nocookie.net/__cb20110512003110/finalfantasy/images/d/d1/Eye-ff1-nes.png Eye]] was originally a [[http://images3.wikia.nocookie.net/__cb20110511064404/finalfantasy/images/f/f9/Evil_Eye_Original_Sprite.png Beholder]]). ''FFI'' and ''VideoGame/FinalFantasyIII'' also used a spell system with "levels" of spells based on D&D's caster classes, but sequels (and later remakes) changed this to [[ManaMeter Magic Points]].
* ''VideoGame/StreetFighterXMegaMan'' was a ''VideoGame/MegaManClassic'' fan game that eventually became officially endorsed by Capcom themselves.
* One of the most popular types of mods for multiplayer first-person shooters is "zombie mode". For ''VideoGame/CallOfDuty: World at War'', Treyarch decided to skip a step and just implement a zombie mode from the get-go - hence VideoGame/NaziZombies.
* ''VideoGame/EscapeVelocity Override'' began as a total conversion to ''Escape Velocity'' (that's actually where there name comes from: the mod developer called it Override since it would override the old game data[[note]]It was 1996. The term Total Conversion hadn't really spread yet.[[/note]], and the name stuck) before the developers of the original adopted it, updated the engine and published it. The same happened for ''Escape Velocity Nova'', which started as an ''Override'' TC.
* The Steam release of ''7.62 High Calibre'' includes the ''[[http://bluesunmod.webs.com/ Blue Sun Mod]]'' and the fan-made extension ''[[http://store.steampowered.com/app/306290/ 7.62 Hard Life]]''. The former is enabled or disabled through checking an option in the Steam's options of the game, while the latter is technically a stand-alone game included in each ''7.62 High Calibre'' purchase.
* ''VideoGame/MountAndBlade: Warband'' DLC ''Viking Conquest'' is basically the mod ''[[http://forums.taleworlds.com/index.php/board,189.0.html Brytenwalda]]'' converted as an official campaign by ''Brytenwalda'' creators.
* ''VideoGame/TheStanleyParable'' was originally released as a ''VideoGame/HalfLife2'' mod with most graphical assets reused from that game, then re-released commercially with original graphics.
* ''VideoGame/ThemsFightinHerds'' started its life as ''[[VideoGame/MyLittlePonyFightingIsMagic Fighting Is Magic]]'', a FightingGame based on the ''WesternAnimation/MyLittlePonyFriendshipIsMagic'' cartoon, by a group of fans called [=Mane6=] using the ''[[GameMaker 2D Fighter Maker]]''. After a [[ScrewedByTheLawyers cease-and-desist]] sent by {{Creator/Hasbro}}, [=Mane6=] decided to continue the project, but [[DivorcedInstallment with original characters and a new universe]]. The creator of the MLP:FIM cartoon, Creator/LaurenFaust, was [[ApprovalOfGod hyped about the original game]] and offered her help in designing new characters to the new game. Additionally, Lab Zero Games gave them a license to use the [[Videogame/SkullGirls Z-Engine]], a professional GameEngine, in substitution of ''2D Fighter Maker'', a GameMaker. Now the group of fans [[TookALevelInBadass constitute an actual company]], ''[=Mane6=], Inc'', and their game will be released commercially.
* ''VideoGame/RWBYGrimmEclipse'' started out as a fan-made effort, but was picked up by Creator/RoosterTeeth and made into an official LicensedGame.
* ''VideoGame/FreedomPlanet'' initially began life as a ''Franchise/SonicTheHedgehog'' fan game. With high-speed platforming, and looping roller coaster level designs, and the character designs are very Sonic-esque, but ultimately grew into its own beast entirely. It was successfully kickstarted and released in 2014, and is getting [[VideoGame/FreedomPlanet2 a sequel]].

* ''Webcomic/{{Drowtales}}'' was originally a ''TabletopGame/ForgottenRealms'' fanfic.
* ''[[Webcomic/DanAndMabsFurryAdventures DMFA]]'' was originally set in the ''VideoGame/{{Furcadia}}'' online chat/roleplaying client. So that would technically make it a fanfic. Early strips have a lot of reference to Roleplaying-terms, internet fads, ect.
* ''[[http://en.wikifur.com/wiki/Freighter_Tails Freighter Tails]]'' was originally called "Haul Trek", but the authors remade it, removing all the ''Franchise/StarTrek'' elements in the process.
* Whatever it might have become, it's fairly obvious from the first strip that ''Webcomic/LookingForGroup'' was originally a ''VideoGame/WorldOfWarcraft'' comic. Things went full circle when the backers suggested a video game was made.
* ''Webcomic/AwkwardZombie'' had a [[http://www.awkwardzombie.com/index.php?page=0&comic=042009 strip about turning itself into an Ascended Fanfic]], but it turned out to be onetime gag and the series went back to using Smash Bros. characters.
** The author pulls strip ideas from the forums pretty frequently, and even has a thread for the purpose.
* ''Webcomic/ArthurKingOfTimeAndSpace'' is based on ''King Arthur In Time And Space'', which in turn was based on ''Franchise/StarTrek''[=/=]''Series/DoctorWho'' crossover fanfic cartoons with the proper names search-and-replaced (Arthur, Lancelot and Guenevere replacing Kirk, Spock and [=McCoy=]; Merlin and Nimue subbing for the Doctor and various companions).

[[folder:Web Original]]
* In October 2012, a fan of WebVideo/AtopTheFourthWall created a backstory for Longbox of the Damned's Moarte on Tumblr, where he was a famous magician that killed his rival to obtain the titular box. Lewis saw this post and liked this so much that he's considering making this the official origin of Moarte.
* ''Literature/ChakonaSpace'' started out as a Star Trek fanfic. It has retained most of the technology and the Caitian race but almost everything else is original by now.
* The ''Roleplay/GlobalGuardiansPBEMUniverse'', the largest and longest-running game of its kind, started out as seven people trading what was essentially ''Franchise/{{Justice League|of America}}'' fan fiction. Then they decided to try their hands at original characters, and the rest was history.

[[folder:Western Animation]]
* The GenderFlip "Fionna and Cake" episodes of ''WesternAnimation/AdventureTime'' were based on WhatIf comics created by the show's character designer, which were in turn based on the RuleSixtyThree images on 4chan.
* A 26th season ''WesternAnimation/TheSimpsons'' episode, "Bart's New Friend", is based on a fan script written by Judd Apatow. The plot is about Homer being hypnotized into acting like a ten-year-old.
* The character of Newtralizer in the 2012 ''WesternAnimation/{{Teenage Mutant Ninja Turtles|2012}}'' came from Executive Producer [[PromotedFanboy Ciro Nieli's]] elementary school drawings.
* ''WesternAnimation/RickAndMorty'' began as "The Real Animated Adventures of Doc and Mharti", a fan parody of ''Film/BackToTheFuture'' submitted to Website/Channel101. When it was taken up by [adult swim], it was retooled to make the ''Back to the Future'' elements much less overt.