"Danger always strikes when everything seems fine." -Seven Samurai
"What's the use of worrying about your beard when your head's about to be taken?" -Seven Samurai
"I'm not dying yet. I have to kill quite a few men first." -Yojimbo
"Dead men tell no lies." -Rashomon
I'm a big Kurosawa fan.
Edit: I guess they don't count, since it's the
American Film Institute's list, but they're worth mentioning.