Favorite Classical song? audio neccesary

[Taso]

http://youtube.com/watch?v=S6yuR8efotI

That's Bach's Cello Suite No. 1 Prelude, its by far my favorite classical song. Especially the last 40 or so seconds, it gets very intense.

I'd love to hear other's favorites, I'm not too familiar with classical music at all. Youtube or some other form of audio is a must here!