Gone Baby Gone
Wow. A very convoluted story line and characters i didn't really know. But boy, was it intense. There was a part during this movie that scared me worse than I can ever remember being scared during a movie. Also adds a nice little bit of moral philosophy that you and your friends can talk about after the movie ends.
Mystic River
Generally pretty meh. Another super convoluted story that worked worse than Gone Baby Gone's, IMO. Penn did a very good job, but I really didn't like his character on a personal level. There were a few loose ends that the ending didn't tie up for me either.