I would like to recommend these films, some of them are underrated, but they are quite good. Unfortunately, they just lacked the hype that some other big films had. The films that I would recommend would be:

-Monster
-The Talented Mr. Ripley
-Big Nothing
-Insidious
-Shutter
-Let Me In

And if you're into crude humor:
-Bruno
-Deuce Bigalow 1 and 2
-The Hangover 1 and 2

(I will edit this list from time to time to add new movies that I want to recommend)