29 days after the sinking of RMS Titanic, a 10-minute-long short film titled Saved from the Titanic (now lost) was released. The leading star and a co-writer of the script was Dorothy Gibson - a genuine Titanic survivor, playing as a girl named Dorothy, and filmed in the same clothes she was rescued in.
Cesar Millan makes an appearance as himself in The Back Up Plan.
A dramatic example: Derek Jacobi plays himself in Hereafter as both the voice of a Charles Dickens audiobook and as a speaker at a literary festival.
Neil Patrick Harris as "Neil Patrick Harris" in the three Harold and Kumar movies. He requested not to be credited "as Himself", to make it clear he's not a drug-sniffing, car-stealing womanizer in Real Life (he is in fact, the complete opposite — an upstanding gentleman and in a stable relationship with David Burtka; i.e. no drugs, no stealing cars, and one guy, not many women). Burtka himself gets in on the act in A Very Harold & Kumar 3D Christmas, using their real-life relationship as a cover for their characters' sordid behavior, and gets the same credits treatment ("David Burtka" played by David Burtka).
Forrest Gump meets many famous figures throughout his travels, some played by actors, but others played by archive footage. Both times he meets the president, it's done using archive footage. Obviously fictional circumstances, since Forrest Gump didn't really exist.
In Full Out: The Ariana Berlin Movie (which is Based on a True Story), the real Ariana Berlin was the gymnastics double for Ana Golja, who played her in the film.
1990's Gremlins 2: The New Batch features film critic Leonard Maltin (who disliked the original Gremlins) in a scene where he discusses Gremlins 2 on a Siskel-&-Ebert style show. After giving the sequel a poor review, a horde of Gremlins storm the set and kill him.
In a later scene, Gremlins hijack the film projector itself, until Hulk Hogan stands up in the audience orders them to quit screwing around and let the movie finish. In the VHS version, the Gremlins record over the tape until John Wayne (recreated through archival footage) tells them off. The novelisation has the Professor Gremlin lock the author out of his office and type a few pages on his typewriter instead.
Bill Murray's appearance in Zombieland was widely promoted as The Cameo, but it actually falls into this territory, since he's in the movie for quite a bit of time (playing himself) and is actually the only other non-flashback speaking character outside of the main four.
Bill Murray again in Space Jam, wherein he eventually fills out the ranks of the Tune Squad to avert a forfeiture of the game. (In fact, the trope applies for pretty much all the live-action stars of the movie, aside from Wayne Knight and a few others.)
The Blues Brothers plays with this, featuring the band members playing themselves. The majority of them were part of the original backing band, and are well known blues and R&B legends, including Steve Cropper, Donald "Duck" Dunn (both of whom are in the Rock & Roll Hall of Fame as members of Booker T and The MG's), and Matt "Guitar" Murphy. Paul Shaffer turns up in Blues Brothers 2000, but he's not actually playing himself — he instead adopts a thick French accent, playing the role of Queen Mousette's aide, Marco. He later takes off the wig and performs with the band, though, for which he gets credited both as Marco and as himself on the end credits list.
Every actor in Coffee and Cigarettes plays themselves, although arguably some of the minor characters may be cases of The Danza.
Funny People features several famous or once-famous comedians and entertainers as friends of the fictional George Simmons, whose career appears largely inspired by that of Adam Sandler, who plays him.
The Andy Kaufman biopic Man on the Moon featured numerous people from Kaufman's life as themselves, including
the cast of Taxi — except for Danny DeVito, who was already playing Kaufman's manager
David Letterman, Paul Shaffer, and the Late Night with David Letterman band, re-creating Kaufman's infamous appearance on Late Night With David Letterman with wrestler Jerry Lawler (also playing himself) — though filmed on the Late Show set, with no real attempt made to make anyone look younger.
The late Miami Dolphins football team owner Joe Robbie played himself in the movie adaptation of Black Sunday in which terrorists are going to attack the Super Bowl. He's interviewed about security at the Orange Bowl by Robert Shaw, who is playing Israeli counter-terrorist David Kabakov.
In Get Shorty, during the filming of the climax of Chili's movie, Harvey Keitel plays himself playing Ray Bones. Also, Penny Marshall as herself, directing said movie.
In Ocean's Twelve, Julia Roberts plays a character, Tess, who is persuaded to pose as Julia Roberts. This plan actually falls apart due to another surprise example: Bruce Willis spots Tess!Julia and eventually is able to figure out it's not Julia Roberts, foiling the Ocean crew's plan.
Paolo Roberto as himself in The Girl Who Played With Fire, second film of The Millennium Trilogy. The Swedish language version, anyway; whether he will be cast as himself in the Hollywood version is yet to be seen.
Fred Niblo, a real MGM movie director, has a comic supporting role in Free and Easy as Fred Niblo, MGM director, who has a world of difficulty in getting Elmer J. Butts (Buster Keaton) to memorize a single line of dialogue.
An unusual mutation can be found in the feature-length version of The Wizard of Speed and Time: the cast list at the end of the film starts with "Mike Jittlov — The Wizard" followed immediately by "The Wizard — Himself".
Attorney Ed McDonald plays himself in GoodFellas when Karen and Henry Hill look to the Witness Protection program; he handled the Hills' case in real life. The Hills' dialogue was taken verbatim from the transcript of their conversation while McDonald ad-libbed his dialogue.
United 93 featured many of the actual people involved in the original events, including Ben Sliney, former U.S. Federal Aviation Administration's National Operation Manager and the man who ordered the US airspace to a National Ground Stop during 9/11. He played himself, reenacting those same events, and does a damn good job of it.
"And introducing Otto [the autopilot] as himself."
Several Major League Baseball players and umpires, as well as numerous sportscasters in The Naked Gun. Special mention to Reggie Jackson as a would-be brainwashed royal assassin.
Weird Al also sings the theme to Spy Hard while wearing a white tuxedo in the opening credits. When his name comes up in the credits for writing and singing the theme song, he points to it.
In the German movieKeinohrhasen, the main character is a paparazzo and sneaks into the engagement party of Yvonne Catterfeld (pop singer) and Wladimir Klitschko (professional boxer). While these two celebrities play themselves, their relationship is entirely made up.
Contagion (2011) has Dr. Sanjay Gupta cameo in an interview with Dr. Cheever.
In Jerry Lewis' The Bellboy, Lewis plays himself and the bellboy Stanley. After Milton Berle (as himself) lectures Stanley, he runs into Jerry Lewis (as himself), and wonders if there can be "two of them." Berle goes off, then Lewis runs into a bellboy (played by Berle), and Lewis does an extended double-take.
In All the President's Men Frank Wills, the security guard who finds the masking tape on the door in the opening scene, is played by Frank Wills, the security guard who actually found the masking tape on the door at the Watergate. A lot of politicians and reporters appear as themselves in archival footage, including President and Mrs. Nixon, Spiro Agnew, Ron Ziegler, Walter Cronkite, etc.
The original Angels in the Outfield included (simulated) newsreel interviews with (actual) famous people concerning whether or not McGovern is actually conversing with angels. Among them is Ty Cobb, who simply says "All I can say is the game of baseball has certainly changed!"
In The Fighter, Micky Ward's trainer/Lowell police sergeant Mickey O'Keefe is played by... Micky Ward's trainer/Lowell police sergeant Mickey O'Keefe. O'Keefe had never acted before and was reluctant to take the role, though Mark Wahlberg was eventually successful in persuading him.
Dale Earnhardt Jr. asks Ricky for an autograph in one scene. He is seen in the garage at Talledega in a deleted scene.
Ricky beats Jamie McMurray by running in reverse.
Both the NASCAR on FOX broadcasting team (Mike Joy, Larry McReynolds, and Darrell Waltrip) and the NASCAR on NBC team of 2005 (Bill Weber, Wally Dallenbach Jr., and Benny Parsons (died 2007)), are present; the FOX team is used for two races in the first half of the movie, while the NBC team is covering the Talladega race at the end of the movie.
There's even a funny moment where an NBC reporter in the stands claims to have spotted Kenny Rogers and Larry Bird on two different occasions, but Weber, Parsons and Dallenbach have a hard time believing him, suspecting he might have had a stroke.
Extremely common in old westerns, especially of the "singing cowboy" variety. Roy Rogers, Dale Evans, Gene Autry, etc. all made many, many films playing characters with their own names.
A variation is seen in Under Siege, where Erika Eleniak's character is introduced to a man by another character by showing him a Playboy centerfold and saying she's "Miss July 1989." While the character goes by a different name than the actress, she was in fact the actual Playmate of that month.
The 1948 Franco-Norwegian film Kampen om tungtvannet (The battle for heavy water) with Jens-Anton Poulsson, Claus Helberg Urbye, Thorstein Skinnarland and HH Halban as themselves.
In The Great Ziegfeld, almost every one of the performers who were still alive when the movie was made were played by themselves. (Eddie Cantor is the exception.)
In Cover Girl (1944), supermodel Jinx Falkenburg has a cameo role as herself. Fifteen other real cover girl models of 1944 also appear as themselves in the Show Within a Show.
Ben Affleck, Matt Damon, Shannon Doherty, Wes Craven, Gus Van Sant and Mark Hamill also all appear as versions of themselves with varying degrees of jerkishness.
The 2010 film Round Ireland With a Fridge, based on Tony Hawks' 1999 book Round Ireland With a Fridge, based on Tony Hawks actually travelling round Ireland with a fridge in 1997, stars Tony Hawks as Tony. The follow-up, 2012's Playing the Moldovans at Tennis, also stars Hawks as himself. (Arthur Smith's role in the book and actual events is taken by Stephen Frost playing himself, rather than have an actor "do" the inimitable Smith.)
Chris Berman plays himself in the 2005 remake of The Longest Yard — and since he's actually calling the game, you're hearing him a lot in the third act. Jim Rome also briefly appears as himself.
Similarly, John Madden and Pat Summerall, respectively the color commentator and play-by-play announcer of Monday Night Football at the time, appeared as themselves in The Replacements (2000)
Pro Wrestlers vs. Zombies features multiple wrestlers (as well as one Penthouse Pet and several members of the production staff) As Themself since the premise is that they were invited to a particular wrestling exhibition before the Zombie Apocalypse starts.
Lawyer and politician Fred Thompson started a prolific acting career in his forties when he was asked to play himself in Marie, about a client of his who fought a parole-bribery scheme.
Offbeat actor John Malkovich plays offbeat actor John Malkovich in the appropriately named Being John Malkovich, although there are several significant differences between the character and the real person, as well as a couple thrown in just to make the point that they're not meant to be exactly the same (for instance, the film makes a point of mentioning that Malkovich's middle name is Horatio, while the real Malkovich's is Gavin).
The movie I Shot Jesse James provides an intriguing In-Universe example. After killing Jesse James, Robert Ford performs as himself in a stage show that shows how he killed Jesse. Of course, this was something the real Robert Ford actually did, so it makes sense to include it within the film.
Played with in Jolson Sings Again, the second of two biopics of singer Al Jolson. The film chronicles Jolson's later life, including the making of the first biopic, The Jolson Story. Actor Larry Parks not only plays Jolson, but plays himself playing Jolson in the filmmaking scenes.
Clint Eastwood's film The 15:17 to Paris: Spencer Stone, Anthony Sadler and Alek Skarlatos, the three American soldiers who heroically stopped a terrorist attack on a French train in Real Life, are played by themselves. As are at least three other people who were on said train.
In the 1923 comedy The Extra Girl, silent stars William Desmond and Billy Bevan appear as themselves.
In Please Stand By, Wendy's four housemates are all played by autistic actors with the same names as their characters.
Stick It features gymnast Nastia Liukin playing herself two years before she won the Olympic All-Around gold. (Liukin is actually not the only real competitive gymnast who appears in the film, but she's the only one to be mentioned by name or play a role in the story; the others are mostly background.)
NBC gymnastics commentators Bart Conner, Tim Daggett, and Elfi Schlegel appear as themselves during the national championships sequence.
In Duck Butter, Naima is hired (and quickly fired) as an actress in a film directed by Mark and Jay Duplass, who play themselves. On her way to the set, she listens to a podcast where the Duplass brothers are interviewed about their filmmaking methods - though Mark and Jay Duplass' characters are simply listed as Mark and Jay with no last names, their last names are mentioned in the podcast heard in the movie, which is an excerpt of a real podcast they were interviewed for.
Chubby the dog from Relative Fear is credited this way.
In Godzilla: King of the Monsters (2019), Godzilla, King Ghidorah, Mothra, and Rodan are all credited as himself/herself, as part of the cast credits while the motion capture performers who brought the kaiju to life were listed as a separate set of credits.
Someone Great: Musicians Questlove and Jessie Reyez appear as themselves at Neon Classic.
Tales of Halloween: Adrianne Curry makes a cameo as herself in "The Night Billy Raised Hell", with Billy and Mr. Abaddon carjacking her and stealing her car.
Ring of Fear is a Non-Actor Vehicle featuring circus owner/lion tamer Clyde Beatty and author Creator/Mickeypillane as themselves solving a mystery at Beatty's circus. Additionally, various members the Clyde Beatty circus appear as themselves performing their circus acts.
In One-Trick Pony, Tiny Tim appears during the Salute to the Sixties, wandering around backstage playing his ukelele.
In Molly (1983), the titular singing dog is credited this way.
In Knocked Up, Ryan Seacrest plays a fictional version of himself and the boss of Alison Scott. Unlike in real life where Ryan enjoys being in entertainment shows like E!, this version of Ryan hates it because he wanted to be a respected TV reporter doing real journalism but got stuck doing tabloid news of celebrities.
In Mad Love (1995), the band 7 Year Bitch perform as themselves during a club scene.
In The Drummer and the Keeper, rock band the Strypes appear towards the end of the movie, when Christopher gets a job as their roadie.
Call Me Bwana: Golfer Arnold Palmer appears during a scene where Matt's party stumbles upon a country club, where Palmer and Matt play golf.
In Magic in the Water, the lake monster Orky, who is played by an animatronic, gets this credit.
In Faceless, actress Florence Guérin plays an actress named Florence Guérin.
Free Guy: Alex Trebek, Lara Spencer (of Good Morning America), and Chris Evans all make cameos as themselves. It's also zigzagged with the cameos made by various YouTube and Twitch streamers, who are credited as playing their streamer handles rather than themselves (e.g. Sean McLoughlin is credited as playing Jacksepticeye).
The film's director Quinn Shephard appears as one of the attendees in the second support group Danni attends where she plays herself, rebuking Danni for not truly having apologized.
Although most of their names aren't mentioned, presumably all the YouTubers that appear in cameos. (Caroline Calloway is, however, mentioned by name).
Duck Butter: Several real people in the film industry appeared as themselves, including both Duplass brothers, Lindsay Burdge and Kumail Nanjiani.
About half of the cast in The Compleat Al are people playing fictionalized versions of themselves — these include "Weird Al" Yankovic's parents Nick and Mary Yankovic, guitarist Steve Cropper, Dr. Demento, Dick Clark, producers Phil Ramone and Rick Derringer, and Al's band members Steve Jay, Jim West, and Jon "Bermuda" Schwartz.
Dear Brigitte: 8-year-old Erasmus has a Celeb Crush on actress Brigitte Bardot and writes her love letters. She shows up in the flesh towards the end when Erasmus and his father go to her house at her invitation.
appears at the end. Anna Q. Nilsson,