Fun Stuff:

Rating: Null/10 (21 November 2001)

Near the end of the film when Sullivan takes Boo back to her room and she is handing him her different toys, one of the toys she hands him is a Jessie doll. Jessie is the Cowgirl in Toy Story 2. If you look even closer you will notice that she also hands him the ball from "Luxo," one of Pixar's first animated shorts.
Watch the end of the credits. Anybody else see all the names on the "Human Child Scream Research Team"? What a cool job. Making kids scream...

Near the end of the film when Mike and Sully throw that Chameleon looking thing out of the door and into a trailer, you can see a Pizza Planet sign in the background. Pizza Planet was the pizza restaurant in both Toy Story films.