People who can do the human pretzel trick always amaze me. I know several guys who can do it.
I think it's funny though, that anytime guys show off doing the trick in front of girls, the first question they ask is "can you s**k yourself"? Of course the answer is usually yes. Which of course leads to the girls daring them to show that trick too.
I can't do the human pretzel thing, but I can do the latter! hehe.