I don't seem to be able to post videos here, but I will always count the scene with Marylin Monroe, in Some Like it Hot, where she is on the railway platform, 'She's like jello on springs' as one of my favourites...
At this point in the movie I was no longer in my seat. I was remembering my grandfather, my questions about being here on earth, and totally transfixed. Then, as the ball dropped, so was I, back to reality.