Penspinning

I worked with a Japanese postdoc on the human genome project in Toronto in 2000. He would constantly be twirling his pen in his hand absent mindedly while he talked to me. I asked him about how he did it and he told me that I should not bother and that he thought of it as a bad habit. A few months later I could do some basic penspinning and it did indeed become a bad habit. In fact my thumb aches while I do it, but still I do it while thinking.
Check these guys out:
World Pen spinning championships from Hong Kong.

H/T Boingboing.