At the current moment my top 10 stands like this:
1: Black Swan - Love Natalie Portman, love the completly fucked up last act. First film I've ever found myself with my mouth open in shock and awe.
2: Magnolia - Tom Cruise is good (Really), best line I've heard in a film (Respect the cock, and tame the ****.) Epic in such a small scale.
3: Trainspotting - One of the darkest comedies I've ever seen, worth it just for the opening monologue.
4: OldBoy - Violent, deranged, brilliant. The final reveal is fantastic and the only film I can think of where the villian is more tragic than the hero.
5: The Lion King - Needs no explanation. The best animated film period.
6: Martyrs - 5 minutes in, shotgun scene. That is all.
7: The Departed - One of my favourite Scorsese films, deep themes and great characters. The pivotal elevator scene is amazing.
8: Gone Baby Gone - A dark film, the conflict between what is right and what needs to be done works great here.
9: Taxi Driver - The breakdown of Travis Bickle and his redemption in the form of a child prostitute. Easily De Niro's best role.
10: 4 Months 3 Weeks 2 Days - The bleakest film ever, the stuff the two main girls go through is horrible and you have nothing but sympathy for them.