Lindy, I COMPLETELY AGREE with you on Adventureland. SO much wasted potential.
As for me...
Frailty: If you've never seen this movie, you should. It's obscure, but very good. Stars Bill Paxton as an axe-murderin' soldier of god. One of those few movies that actually manages to surprise you with the "twist" at the end, too. Well, back when I first saw it, anyway. Still holds up today, there are scenes that are kind of disturbing, but not in a "Jacob's Ladder" kind of way. More a "this is uncomfortable" kind of way.