I have a skill that I am not sure I want to have. When you twiddle your thumbs, typically, your thumbs go in circles following each other. I can twiddle in such a way that is opposite. They pass each other. If you start them at the top, your thumbs pass each other at the bottom. The problem is that humans are not supposed to be able to do this. What is worse, chimpanzees can.

Too many bananas?