This is a really tricky list. I used to have a list of 200+ movies, but then I discovered friends.
10. Vanilla Sky
Plenty of people dislike or even hate this movie. I don't think the theme is too unique, but it does a wonderful job of portraying the consequences of living the dream.
9. The Dark Knight
I love comic books and Batman Begins was a paradigm shift. I couldn't imagine how the Dark Knight could measure up, but it exceeded the first in almost every way. The entire movie was about escalation. The relationships were more strained, the gadgets were more extreme, the consequences more dire. Christopher Nolan may be my favorite director. (The Prestige and Memento are both fantastic)
8. Gangs of New York
Picture really says it all.
7. Meet Joe Black
A buddy of mine was in a dead-end relationship that no one could seemingly talk him out of. We tried everything to open his eyes to the fact that he wasn't happy and he had to make a change. I figured it was a lost cause and time passed. One day he came over and Meet Joe Black was on. We didn't talk and after the movie just simply got up to leave. He paused by the door and said that he needed to go call his girlfriend and break up with her. I never asked him what about the movie solidified things for him, but Claire Forlani didn't hurt.
6. Dark City
Probably the most obscure movie on the list, Dark City isn't for everyone. It's a murder mystery with a sci-fi theme. Some outstanding questions are asked and this movie started a one-sided 10 year love affair with Jennifer Connelly.
My list of 10-30 is probably more popular, with movies like Office Space, Breakfast Club, ... crap... how do I not have the Departed in the top ten?? Ugh, this was a terrible idea.