Ratzenberger, best known as mailman Cliff Clavin for 11 seasons on Cheers, is Pixar’s lucky charm: the only vocal talent to appear in all 10 of the studio’s features. Aside from his P.T. Flea here, he played Hamm the Pig in the Toy Story pictures, the Abominable Snowman in Monsters, Inc., part of the fish school in Finding Nemo, the supervillain Underminer in The Incredibles, a whole fleet of vehicles (including such self-referential characters as Hamm Truck, P.T. Flea Car and the Abominable Snow Plow) in Cars, Mustafa in Ratatouille, a lovestruck man in space in WALL-E and a construction foreman in the new Up. Usually Ratzenberger plays the plebeian skeptic, but in A Bug’s Lifehe lends an entrepreneurial zest to a flea who’s always angling to get rich quick. “I’m gonna be the richest flea in the land,” he sings. “Ka-ching! The streets will be paved with golden retrievers!”