I'm definitely heading out to see Sin City this weekend. I'm totally unfamiliar with the comics, but from what I've heard, the movie is the single comic movie to have directly mirrored the comic in every way, including background, layout, and for the most part, dialogue. Of course, I guess it kinda helped to have the author right there the whole time. All in all though, I'm psyched to see it, and I've heard nothing but good about it.
I like Pi, Requiem more though. It was like a better-done Pi, with a better-done point. Not to say that I didn't understand what Pi was trying to put across and express, but I just didn't feel it was done very well.
~kov.