Ronald McDonald: The Washington D.C. version of Bozo The Clown, played by Willard Scott, was so popular public appearances would require police to direct traffic. After the show was cancelled, local franchise owners asked Scott to create a similar character to continue the promotion. Ronald McDonald was born.
The original incarnation of McDonaldLand was a blatant copy of the cast and setting of Sid and Marty Krofft Productions' 70s-era children's show H.R. Pufnstuf. The Kroffts (who had turned down an earlier request from McDonald's to license the Pufnstuf characters for advertising) sued and won, forcing McDonald's to not only pay damages, but to dramatically retool McDonaldLand.
The Bombardier, a Large HamNapoleonic Wars soldier played by Rik Mayall in adverts for Bombardier Real Ale, is what Lord Flashheart would have been if he'd appeared in Blackadder the Third, except he says "Bang on!" rather than "Woof!" Mayall even uses the same voice.
When director F. W. Murnau sought to make a movie out of Bram Stoker's book Dracula, but was unable to secure the rights, he made the movie anyway as Nosferatu, changing the names of the characters. (Dracula, for example, became Count Orlok.) In this case, though, the attempt was unsuccessful: Stoker's widow sued for copyright infringement and won, bankrupting the production company... and getting an order that all copies of the film be destroyed. The movie survived through piracy.
A few in Sky High, but the most obvious is Layla, being similar to Batman's villainess Poison Ivy. She's a redhead, she controls plants, she always wears green, she's very environment friendly, etc. — except she's a good gal.
Detective Anna Ramirez in The Dark Knight was originally supposed to be Renée Montoya, but her name was changed at the last minute because her behavior in the film didn't match that of the animated and comic book character. Montoya is an honest cop, while Ramirez is corrupt and works with the mob.
By the same token, Det. Wuertz was supposed to be another Batman staple, Harvey Bullock. Bullock is at worst, a Jerk with a Heart of Gold, whereas Wuertz is also on the take, and is subsequently killed by Two-Face.
The character of Doctor Lazarus is Spock, the alien on the team, whose actor is haunted by the success of his character and its fictional culture.
Commander Taggart is captain Kirk, the hammy star of the show and a Large Ham.
Tech Sgt. Chen, although not Scottish, is the equivalebt of Scotty, (badly) operating their transpo... sorry, "digital conveyor".
Exceptions are Lt. Laredo, the prodigy child crew member (there was no such role in Star Trek, although The Next Generation had Wesley Crusher), and Lt. Madison who repeats everything the computer says (Lt. Uhura in TOS was in the front line of black, and female, emancipation).
The family is very nearly the Fantastic Four: Mr. Incredible is the Thing, Elastigirl is Mr. Fantastic, and Violet is the Invisible Woman. Only Dash lacks a direct parallel, though he's certainly Hot-Blooded enough to be a match for the Human Torch. The ending shows Jack-Jack has highly variable superpowers (among these, setting himself on fire like the Human Torch), and Franklin Richards, the child of Mr. Fantastic and the Invisible Woman had very ill-defined but vast superpowers. Even their costumes and name (Fantastic/Incredible) are similar. Their villain, Syndrome, is a somewhat more rotund Doctor Doom, a villain whose primary superpowers are simply being so good at super-technology that his super-suit is more powerful than the family combined. Syndrome also has Doctor Doom's 'petty grudge blown WAY out of proportion' motivation for his enmity as well.
Dash is basically The Flash and even calls himself "The Dash" when he gets his suit.
Frozone is basically Iceman from the X-Men comics as played by Samuel L. Jackson. They even have the same way of getting from place to place: creating ramps of ice to skate everywhere.
In a more extreme example, Gazerbeam and The Underminer basically areCyclops and the Mole Men in all but name. The DVD special features on the minor heroes in the movie even parodies Cyclops' infamously bland personality by having Gazerbeam be an incredibly dull person.
It even extends to the comic, which has featured among the expanded rogues gallery a Gorilla Grodd expy and aliens resembling the tentacles.
The Hammer Horror film X the Unknown was originally intended to be a sequel to The Quatermass Xperiment. However, they couldn't get the rights to the character of Bernard Quatermass at the time, so they made up a new character called Adam Royston. He is a Science Hero with the same general mannerisms as Quatermass, the only major difference being that his specialty is nuclear physics, not rocketry.
The Buddy Holly Story had a fictionalized version of the Crickets (two members instead of three, names changed) because the real-life Crickets had already signed onto a different Buddy Holly project.
The conspiracy-laden 1980s stinker, Down on Us aka Beyond the Doors about how the CIA killed Jimi Hendrix, Janis Joplin, and Jim Morrison, you notice that Morrison's band is never mentioned by name and have no resemblance to Manzarek, Kreiger, or Densmore (not to mention, all of the songs in the film are original songs, which sound nothing like the songs made famous by said artists.)
Officially, The Godfather isn't about the Mafia at all. The story goes that when the real Mafia began making complaints and threats, the filmmakers compromised, removing all references to "the Mafia" and "Cosa Nostra". So the film is actually about a fictitious crime organisation that just happens to be based around five fictitious Italian-American families – it’s usually referred to as "the Five Families" when mentioned on screen.
Averted in Part II, where during the senator hearings, the words Mafia and Cosa Nostra are mentioned multiple times (here by an outsider).
A series of El Látigo ("The Whip") films were produced in Mexico. El Latigo is a very close imitation of the famous gringo-created hero of Old California, Zorro.
BBV seemed to specialise in Doctor Who Ersatzes (see also under Radio):
The Stranger was a direct-to-video series starring Colin Baker (who played the Sixth Doctor on the show) and Nicola Bryant (Peri Brown) as "The Stranger" and "Miss Brown", respectively.
While BBV eventually did get licensing rights to various Doctor Who monsters, the Big Two remained exceptions. They never attempted fake-Daleks, but the Cyberons are, well, Cybermen.
BBV eventually self-parodied this, with a video called "Do You Have A Licence To Save This Planet?" in which a swarm of Doctor Who monsters (and the Cyberons) are fought by Sylvester McCoy as ... the Chiropodist.
In the original books, the characters in The Snapper and The Van were the same family as in The Commitments. Due to Fox owning the rights to the Rabitte name, they were different characters. Especially glaring is the fact that Colm Meaney plays the father in both The Snapper and The Van, but is ostensibly playing different characters.
Chapel was replaced by a similar character named Jessica Priest in the live-action Spawn movie. This is due to Chapel being owned by Rob Liefeld, since he originated in Youngblood.
In the 2000-2005 Left Behind film series, Ivy Goldberg of Global Network News is one for Global Weekly secretary Alice Nelson from the books, who also gets confused for being Buck Williams' secret fiancee.
Live Action TV
The Tick replaced Die Fledermaus and American Maid, who were in the animated cartoon but not the original comic book, with Bat Manuel and Captain Liberty.
Whistler, who appeared in a few Season Two episodes of Buffy the Vampire Slayer, was supposed to be a main character on the spinoff Angel. Since the actor who played Whistler was unavailable at the time, the very similar character Allen Francis Doyle was created instead.
Comparisons between Al Swearengen of Deadwood and Silas Benjamin of Kings are pretty inevitable: Both are played in the same highflown style by Ian MacShane; both are amoral and ruthless in attempting to maintain their grip on power but affectionate to those close to them, and both have a tendency to slip into lofty monologues. Except for their different wardrobes and Silas' network-mandated inability to curse like Swearengen, they're essentially the same character portrayed by the same actor.
Star Trek: Deep Space Nine was created with the intent to include Michelle Forbes' recurring character from Star Trek: The Next Generation, Ro Laren, but the actress declined to star as a regular in the series. So the character of Kira Nerys was created as a near-identical substitute (abrasive personality, lack of trust in Starfleet).
And Star Trek: Voyager went as far as to cast the actor who had played Nicholas Locarno in TNG's "The First Duty" before changing the character's name to Tom Paris and altering his backstory to be more sympathetic.
Though Word of God has flip-flopped on whether this was done because Locarno was unrepentant and therefore unsympathetic, or because they didn't want to have to pay royalties to the writer of "The First Duty".
Parodied on 30 Rock when Jenna intends to star in a biopic about Janis Joplin, but because of legal issues, the pic will be about a Janis Joplin facsimile called Jackie Jormp-Jomp.
The BBC has an example combined with Danza in the case of Happy Ever After. When its creator decided that it had run for long enough, he declined to write any more episodes and eventually jumped ship, retaining the rights to the show's format as he did. So the BBC took the central couple from Happy Ever After, changed their surname and character bios, put them in another suburban house, and carried on from there. Terry Fletcher (played by Terry Scott) and his wife June (June Whitfield) became Terry and June Medford in the imaginatively-named BritcomTerry and June. If that wasn't enough, the characters Terry and June are near-identical expies of Ron and Vera Baines, the couple that Terry Scott and June Whitfield played in the feature film version of earlier suburban BritcomBless This House.
In The Adventures of Superboy, a super strong alien woman named Neila, who pursued Superboy romantically, appeared to be an ersatz version of the comics' Maxima.
Parodied in Psychoville when in a pantomime production of Snow White, the director has to remind his cast that they changed the names of the dwarves (to "Prof", "Blusher", "Sniffy", "Smiler", "Snoozer", "Grumbly" and "Loopy") so as to avoid being sued by Disney.
Smallville had Captain Ersatzes for a shockingly-large number of DC characters. Adam Knight was Bruce Wayne, Gloria was Poison Ivy, Vordigan the Dark Archer was Merlyn, Pete Ross ended up becoming a Captain Ersatz of Plastic Man (or Jimmy Olsen as Elastic Lad)...the list goes on and on. One episode even had Lois cosplaying as an in-universe Captain Ersatz of Wonder Woman!
That same episode had a boy transformed by a magic comic book into Warrior Angel. Whereas Warrior Angel was always an Expy of Superman (with his nemesis Devilicus as an Expy for Lex), this "Warrior Angel" was a clear one of Captain Marvel.
Ten Items Or Less has a parody of this trope where the characters create a "Star Trok" Convention with "Blingons and Blomulans" (and Special Guest Jolene Blalock) so they don't get sued by Paramount.
Rhyme And Reason, an ABC game show from 1975, was a Captain Ersatz of CBS's Match Game in that it had two contestants trying to match words (the rhyming word of a poem) with a panel of six celebrities.
In 1961, Goodson-Todman created a Captain Ersatz of its own show The Price Is Right with Say When!!, which had two contestants selecting items from a pool of merchandise and trying to not go over a target value. In turn, 1975's Give-N-Take was an ersatz Say When!! with a spinning arrow. When G-T revived The Price Is Right in 1972 for CBS and nighttime syndication, they turned it into an ersatz Lets Make A Deal.
In Community, Britta introduces Abed to long running British series Inspector Spacetime who is Captain Ersatz to Doctor Who with a constable instead of a companion, red telephone booth instead of a blue police call box and Blorgons instead of Daleks.
Word of God says that in-universe, Dr. Who is a ripoff of Inspector Spacetime.
The Yardbirds ' 1966 song "Stroll On", is this of their version of "The Train Kept A Rollin'". The maker of the movie Blow Up wanted to use "The Train Kept A Rollin'" for the soundtrack, but there were legal issues preventing it from being released outside the US. As a result they recorded the blatant copy "Stroll On" for the soundtrack, under the guise of it being an original song. The song became quite popular and appeared on a number of compilations.
Iced Earth's Cast In Stone is Written On The Walls with new lyrics and reduced instrumentation, as Gene Adam (who wrote these parts) did not allow the band to use them. However apart from this, the backing track is identical to the original version. It is debated amongst fans if this constitutes a new song or not.
During the late 1920s and early 1930s, the King Features Syndicate did several copycats of the Chicago Tribune strips, with Little Annie Rooney being an ersatz of Little Orphan Annie and Dan Dunn being Hearst's answer to Dick Tracy.
Another was The Nebbs (a copy of the Tribune's Gumps), created by Sol Hess, who assisted Sidney Smith (creator of The Gumps) during the early 1920s.
Doonesbury: Uncle Duke was Garry S. Trudeau's tribute/homage to Raoul Duke, Hunter S. Thompson's alias. Thompson for two decades was so upset he refused to read the comic.
The Adventures of Aaron once ran a strip with "The Ghost of Calvin". A couple footnotes make it clear: "Any similarities between Ghost of Calvin and Calvin and Hobbes is purely coincidental." See it here.
In the comic strip For Better or for Worse, it originally seemed as if the artist had intended to pair Liz of with her next door neighbor, Christopher; when he and his family were dropped from the strip, Mrs Johnston altered his serial number and created Anthony Caine.
In Frazz by Jef Mallett, the title character, Frazz is a grown up expy of Calvin from Calvin and Hobbes, both in personality and in artistic design; Mallett says that Bill Watterson is a great influence, but that the similarities are unintentional.
Bally's Eight Ball featured two teens clearly modeled after "The Fonz" and "Pinky Tuscadaro" from Happy Days. Paramount Television and CBS were not amused.
One of the passengers in Williams' Taxi is "Lola", a dark-haired copy of Marilyn Monroe. She was originally blonde and named "Marilyn" until management requested a last-minute art change to avoid a potential lawsuit.
Ray Lloyd was dressed up as the not-quite-Sub-Zero wrestler Glacier (a character who has since popped up in CHIKARA, making for a better fit.)
For awhile WCW had a lot of expies of celebrities wrestling, which created a bunch of strange dream fights. For instance it is unlikely that Prince would ever have fought Liberace, but now you can see what it would have looked like with The Artist Formerly Known as Prince Iaukea and The Maestro.
Johnny B. Badd baby, whooo!
The Friday the 13th movie character Jason Voorhees got into the act as well.
The first was Jason the Terrible (Karl "Butch" Moffatt), a creation of Bruce Hart in the dying days of the old Stampede Wrestling promotion in Calgary in the late 1980s, with his manager the Zodiac (Barry Orton- Randy's uncle) under a mask, and who can be seen here. There have been several other wrestlers who have done the Jason gimmick since.
The Aces & 8s stable in TNA is pretty much a wrestling version of Sons of Anarchy, right down to their attires, logos, and music being inspired by said series.
BBV's Audio Adventures in Time & Space, starring Sylvester McCoy as "The Dominie" (originally "the Professor") and Sophie Aldred as "Alice" (originally "Ace"), Ersatzes of Doctor Who's Seventh Doctor and Ace (also played by McCoy and Aldred) actually attracted enough attention from the BBC that they had to hurriedly makes some characterization changes, including the new names. (Note that Ace always called the Doctor "Professor").
Another line of BBV audios starred Nicholas Briggs (who had previously played the Doctor in non-commercial fanvids) as the Traveler.
Big Finish Doctor Who isn't allowed to use any characters, monsters or Doctors who appear exclusively in the 2005 Re Tool series, so resorts to this on occasion - Noel Clarke (who played Mickey, a companion of the Ninth and Tenth Doctor) shows up playing a very similar character to Mickey in some stories, and Genre ShiftBrit Com episode "The Kingmaker" featured a character who used the Ninth Doctor's Catch Phrase, was described by the other characters as having "big ears", and played by an impressionist imitating his voice and mannerisms. David Tennant also had a prominent role in the "Dalek Empire" series, before getting cast as the actual Doctor.
Another technique used to sneak Nu-Who characters past the copyright radar is to use cast members from the new series in Big Finish's non-Doctor Who ranges. For an example, their audio adaptation of Frankenstein features Arthur Darvill (who played the Eleventh Doctor's companion Rory) as Frankenstein, Nicolas Briggs (who plays the voice of the Daleks) as the Monster, and Georgia Moffett (who played the Doctor's Opposite-Sex Clone Jenny in "The Doctor's Daughter", the real-life daughter of Fifth Doctor Peter Davison and the wife of Tenth Doctor David Tennant) as Elizabeth.
The primary setting of Mutants & Masterminds, Freedom City, is filled with Captain Ersatzes of the characters from Astro City, who in turn are mostly obvious equivalents for famous DC and Marvel superheroes. The Freedom City sourcebook even hangs a lampshade on this by ending with art of a road sign that reads, "You are now leaving Freedom City, please drive carefully", mimicking the ending tag from the Astro City comics.
In a picture in the 3E Hero's Handbook, there's even a character wearing a shirt that says "Ersatz" on the front.
Likewise Champions has many far too many to list: Defender = Iron Man, Doctor Destroyer = Doctor Doom (or occasionally Apocalypse), Foxbat = the silver age Joker. It also has Ersatz cities: Hudson City = Gotham, Millennium City = Metropolis.
Palladium Books' Heroes Unlimited states that one of the goals behind making the game was to allow players, if they wished, to make characters based on their favorite superheroes from the comics. While it doesn't flat out tell you how to, the names of various superpowers make it pretty obvious (and easy) to make, for example, a Wolverinenote Healing Factor + Heightened Sense of Smell + Claws + Indestructible Bones or Spider-Mannote Adhesion + Heightened Sense of Awareness + Swing Line clone.
Looking for 1980s cartoon Captain Ersatzes, then you won't be surprise that Cartoon Action Hour has more than its fair share. For I.E, the Black Widow from "Strikeforce Freedom" is a blonde version of The Baroness from G.I. Joe.
The Swedish superhero game Supergänget (published in English as Supercrew) features some among their quick examples - The Weasel (Wolverine, but female), The Tomani (Incredible Hulk with a Shout-Out to children's author Christine Nöstlinger) and Tapir Man (Rhino, and being a caricature of a friend of the author), among others.
The card game Sentinels of the Multiverse features homages to several well-known comic book characters, like Legacy (Superman), the Wraith (a female Batman), Tempest (Aquaman with hints of the Martian Manhunter) and Ra (Thor).
Various members of the Dungeons & Dragons pantheon are based on deities from fantasy fiction.
Gruumsh, with his orcish followers and eye-shaped holy symbol, is clearly meant to invoke The Lord of the Rings' Sauron.
Likewise, some D&D deities are based on deities from old mythologies. The game writers could easily have gotten the rights to these characters, but presumably felt that creating their own analogue deities would give them more freedom, and that any way to avoid making D&D look like a neopagan cult couldn't hurt.
The majority of the cast of Sonichu consists of Sonicrecolors. Firstly, Sonichu is an ersatz that the author made sometime in the 1990s when a teacher wouldn't allow him to use Sonic the Hedgehog or Pikachu in a class project due to copyright. There's also Simonla Rosechu, who was originally a (male) Fan Character created by a troll who's a fan of Tengen Toppa Gurren Lagann, but Chris decided to change his gender and turn him into a Rosechu before using her in the comic. Add in two characters based off Zelda (Zelina Rosechu, Clawdorf and Darkbind Sonichu), Sailor Megtune and various others. The only characters who seem to be completely original are Kel, a generic Pokémon trainer, and Count Graduon, the Anthropomorphic Personification of Chris's high school graduation.
Attack Of The Super Wizards stars public domain characters, one of whom, Stardust, was created to be an ersatz Superman. The comic also includes ersatz versions of Krypto, Lois Lane, Batman, Wonder Woman, Cthulhu, Alan Moore, and others.
Aldran is a magic user like Vaarsuvius and has the Deadpan Snarker personality of Vaarsuvius and Roy and an Evil Twin (or possibly Good Twin), just like Elan.
Kerris and Lana are both pretty much Haley, except the first is a Tiefling and the second is a vampire, and Kerris' species also makes her quite similar to the villain Nale's succubus girlfriend, Sabine.
Batdragon of Dragon City and his daughter Batdragongirl both fit this trope as they're parodies of Batman and Batgirl (respectively).
And Zzdtri is a spoof of Drizzt, and his status as an Overused Copycat Character. His first appearance has him dragged away by copyright lawyers, but he later returns having realized that parody is protected under Fair Use.
Anyone who writes for The Erotic Mind Control Story Archive is forced to use this trope in their fiction. See, Warner Bros. slammed the site with legal threats in 1998 due to fan fiction on the site that used their characters. The site's webmaster deleted almost every single fanfic from the site and hasn't accepted any new fanfics since. Only four fanfics survive on the site to this day, but three of them are Star Trek, and the fourth one is The X-Files, both franchises that are not owned by Warner. Also, all four fics are legacy; they date from before 1998. To that effect, in the stories labeled "CB: Comic Book Superhero" and "SF: Science Fiction", you'll probably see characters that look exactly like Wonder Woman and Captain Picard, but have completely different names. The EMCSA also overlaps this trope with Fandom Berserk Button, as there are several other kinds of fiction banned from the site; however, on the official forums, there's a link to the Internet Archive Wayback Machine that you can use to get at the deleted stories.
Speaking of The Irate Gamer, one of his recurring characters is Wilkins, who is Wilson from Home Improvement in all but (similar) name. He actually debuted as Wilson in the review of the Super NESHome Improvement video game, appropriately enough.
Quite common in Original Slash. Shousetsu Bang* Bang, an original yaoi magazine on LiveJournal, even has this as one of its rules - "If you're hung up on characters that don't belong to you, change their names and details, AU them, and the Editor will be happy to think of you as one of those people who always draw their seme to look like Youko Kurama."
Also, Celsan Automotive LLC on NationStates, who appear to be a sort of copy or Homage to Nissan, Holden, Peugeot, Opel, Chevrolet in one. Possibly an Expy too.
Ever since Marble Hornets came up with totheark, nearly every single Slender Man-related blog/video series has had a similar character.