What Is Your Favorite Movie Scene Of All Time??

From Parenthood, when Gil(Steve Martin)'s grandmother puts parenthood in perspective:

[Gil has been complaining about his complicated life; Grandma wanders into the room]
Grandma: You know, when I was nineteen, Grandpa took me on a roller coaster.
Gil: Oh?
Grandma: Up, down, up, down. Oh, what a ride!
Gil: What a great story.
Grandma: I always wanted to go again. You know, it was just so interesting to me that a ride could make me so frightened, so scared, so sick, so excited, and so thrilled all together! Some didn't like it. They went on the merry-go-round. That just goes around. Nothing. I like the roller coaster. You get more out of it.