Passage: Lee became a figurehead and public face for Marvel Comics. He made appearances at comic book conventions around America, lecturing at colleges and participating in panel discussions. Lee and John Romita Sr. launched the Spider-Man newspaper comic strip on January 3, 1977. Lee's final collaboration with Jack Kirby, The Silver Surfer: The Ultimate Cosmic Experience, was published in 1978 as part of the Marvel Fireside Books series and is considered to be Marvel's first graphic novel. Lee and John Buscema produced the first issue of The Savage She-Hulk (February 1980), which introduced the female cousin of the Hulk and crafted a Silver Surfer story for Epic Illustrated #1 (Spring 1980).He moved to California in 1981 to develop Marvel's TV and movie properties. He was an executive producer for, and made cameo appearances in Marvel film adaptations and other movies. He occasionally returned to comic book writing with various Silver Surfer projects including a 1982 one-shot drawn by John Byrne, the Judgment Day graphic novel illustrated by John Buscema, the Parable limited series drawn by French artist Mœbius, and The Enslavers graphic novel with Keith Pollard. Lee was briefly president of the entire company, but soon stepped down to become publisher instead, finding that being president was too much about numbers and finance and not enough about the creative process he enjoyed.

Question: What special thing did Stan Lee do in each of his Marvel films?
cameo appearances