I thought this was interesting....

If your index finger and ring fingers are roughly the same length, then your more naturally inclined to be an athlete. Researchers studied 607 females and found that those whose fingers were closest in length were more likely to be skilled at sports, especially running.

I wonder how much constitutes "close"?

That's a good question--how much variation can there be? My ring finger is about 3/8" shorter. I am not a natural jock, so "close" must be less than 3/8"!