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.
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