What's your favorite dance scene in a movie?

I love the scene in Risky Buisness when he dances in his shorts and
also the Breakfast Club when they all dance in the library...whats
your favorite dance movie scene? (please add link if possible)

http://www.youtube.com/watch?v=G2UVsyVLLcE

http://www.youtube.com/watch?v=gRMrMzw0t20