Years ago my mom and dad and I were watching Johnny Carson. One of his guests that night did a lot of interesting things with his hands. Then he started clapping with one hand (not that snapping thing the kids do now, and not clapping it against anything else). My mom and dad said how neat that was. I said, "What's the big deal?" One of them said, "Oh yeah, like you can do it?" I said, "Of course, I thought everyone could." I really did think everyone could do it, as it comes naturally to me, using either hand. They were really surprised. The kids at school loved when I did it. I have had two students in the last 12 years who could do it. I have tried teaching it, but apparently it can't be taught (or I haven't come across someone who can learn it).
Oh yeah, I can turn my arms kind of backwards, but not as much as I used to.
P.S. This sometimes makes me wonder if there is something else that I can do that most people can't, but it's not really like you can ask people that!