Life imitating art, Chuck Yeager waits to offer Harry Shearer a whiskey in THE RIGHT STUFF (1983). Major General Yeager broke the sound barrier on October 14, 1947. © Warner Bros.

BORN ON THE FOURTH OF JULY is a 1989 American film adaptation of the best selling autobiography of the same name by Vietnam War veteran Ron Kovic. The film begins with Ron Kovic's childhood during a summer in Massapequa, New York. While attending a Fourth of July parade, Ron Kovic himself (w/mustache) appears as WWII veteran in a wheelchair. © Universal Pictures

Moe Black's brother Fat Andy, portrayed by real-life-cop-on-mafia-payroll-now-in-jail-for-life Louis Eppolito. GOODFELLAS (1990) © Warner Bros.

In JFK (1991), the real Jim Garrison, a severe critic of the Warren Commission, played Supreme Court Chief Justice Earl Warren himself, during the scene in which he questions Jack Ruby in a Dallas jail. Kevin Costner played Garrison in the film. © Warner Bros.

Perry R. Russo, one of the sources for the fictional character "Willie O'Keefe", appeared in a cameo role as "angry bar patron" in JFK (1991). Kevin Bacon played Willie O'Keefe, a composite character who testifies that Clay Bertrand and Clay Shaw are the same person and that he knew David Ferrie, and had met Oswald. © Warner Bros.

In JFK (1991) Dutch journalist Willem Oltmans had a brief appearance as Lee Harvey Oswald's pal, Baron George De Mohrenschildt. In the Sixties, Oltmans had become convinced (based on a conversation with a Dutch "clairvoyant" named Gerard Croiset!) that De Mohrenschildt had masterminded the Kennedy assassination. He caused the Baron a fair amount of trouble before the latter's tragic suicide in 1977. © Warner Bros.

After spending days in space after a technical malfunction, Jim Lovell (Tom Hanks) and his crew finally touch down on earth. When the crew is picked up by the USS Iwo Jima (LPH-2), Tom Hanks is congratulated by the real Jim Lovell as the Navy Captain in APOLLO 13 (1995). Lovell was not credited for his very brief time onscreen toward the end of the film. © Universal Pictures

Two non-actors trying to act in THE PEOPLE VS. LARRY FLYNT (1996). On the left is political consultant James Carville as attorney Simon Leis and the Judge is Hustler publisher Larry Flynt, whose life story this film is based on. The scene is of Flynt's (Woody Harrelson) first trial in 1977, when he was convicted on obscenity charges. © Columbia Pictures

In Cameron Crowe's semi-autobiographical ALMOST FAMOUS (2000), Patrick Fugit peers into a cab with "Rolling Stone" editor Jann Wenner reading a paper. ALMOST FAMOUS is based on Crowe's experience as a teenage writer for "Rolling Stone" magazine. The film is based on Crowe's experiences touring with rock bands Poco, The Allman Brothers Band, Led Zeppelin, The Eagles, and Lynyrd Skynyrd. In a Rolling Stone article, he talks about how he lost his virginity, fell in love, and met his heroes, experiences that are shared by William, the main character in the film. © DreanWorks Pictures

The real Erin Brockovich as "Julia R.", the waitress in the film about her legal fight against Pacific Gas and Electric Company (PG&E;). "Julia R" is referring to Julia Roberts, who portrayed and won the Oscar for Best Actress in ERIN BROCKOVICH (2000). © Universal Pictures

THE WOLF OF WALL STREET (2013) was based on Jordan Belfort's memoir. He was convicted of fraud crimes related to stock market manipulation and running a penny stock boiler room, for which he spent 22 months in prison. Belfort himself appears at the end of the film as the Auckland spokesperson introducing "himself" Leonardo DeCaprio. © Paramount Pictures