Pentix is a site devoted to the art of pen spinning. I've seen guys doing this, and was surprised at how hard it seemed when I tried it myself. Now that this site exists, maybe I'll try again. Something annoying and distracting to work on during meetings!

Looked at the right way, this is really a specialized, office-compatible form of contact juggling, the art of juggling where you keep objects in contact with your body rather than throwing them around.