John Ratzenberger

John Ratzenberger has performed the voice of a character in every feature-length Pixar film to date. His roles have included Hamm in Toy Story and Toy Story 2, P.T. Flea in A Bug's Life, the Abominable Snowman in Monsters, Inc., the Fish School in Finding Nemo, the Underminer in The Incredibles, Mack in Cars, and Mustafa in Ratatouille.

He is, however, probably most famous for his Emmy-nominated role as Cliff Clavin on the television series Cheers.