I've been thinking about this for a while and figure this would be the place to ask everyone:
What is your favorite box office bomb? I'm going to say The Adventures of Pluto Nash is my favorite. No matter what critics or anyone else says, that movie is fantastic! My favorite near-flop has to be UHF. The humor just hits me every single time.
Edit: I did not expect this topic to blow up like it did. There's no way I can get to everyone so I'll just say here that I appreciate all the input. I've seen some great mentions and even a few films I've yet to watch.