Definitely a movie adults... (Score 3, Interesting)

err, intelligent slashdotters can enjoy. Besides the animation and the obvious gags, the film touched on a number of themes, including:

1. The absurdity of the children's mythology of monsters. The film turns this on its head by having the monsters believe (incorrectly) that a child's touch will kill them (You get this real early on; this is a very insignificant spoiler).

2. The evils of big business, and how obvious smart solutions are both easier and usually ignored (Take THAT, MPAA).

3. Usually, a children's movie like this has a hero who has to overcome some evil force, which the hero conquers with the help of the good guys. ...

****MINOR SPOILER WARNING****

...But in Monsters, Inc., all but the hero's closest friends, are unknowingly part of the evil force, and it is the hero's responsibility to find a moral solution to both his personal and the town's problems, and then persuade the company to stop its evil and behave morally.

4. The possible negative effects of fame.

I especially liked how the seemingly self-centered Mike didn't mind being obscured on TV or on the magazine; it showed his flaw was in his inferiority complex, not in his self-centeredness, and made the ending a solution to his inferiority complex.