3. Monsters Inc.
Pixar is notorious for filling their films with in-joke Easter eggs, most notably including the number "A113", the number of the CalArts classroom that many Pixar employees attended when they were computer animation students, on numerous props and references. To single out just one Pixar film though, Monsters Inc. paid tribute to stop-motion genius Ray Harryhausen, the man behind the old-school special effects of such classics as Jason and the Argonauts and Clash of the Titans (the original, not the CGI-infested, godforsaken remakes). The name of the chic restaurant that Mike Wazowski takes would-be girlfriend Celia to is named Harryhausen's.