check out Trainspotting, Requiem For A Dream, Primal Fear, Seven, Bone Collector (with the woman of my life, Ang. Jolie), Vanilla Sky, The Usual Suspect and for some ethnic flavor, Amores Perros.
i'm sorry guys but i will have to say that all those war/fighting/patriotic movies just don't do it for me. get a movie that'll twist your head around or make you think about things you never imagined and movies that'll shake your emotions like a milkshake...