I had heard what I considered to be an urban legend that the ratio of a woman's index to ring finger indicates whether women are likely to engage in casual sex and the sexual orientation of men. Turns out the research has been done and maybe it's not an urban legend after all. Oh and for those of you wondering, my ring finger is about 10mm longer than my index finger - could possibly explains why I'm such a fast sprinter.

Are 2D:4D Finger-Length Ratios Related to Sexual Orientation? Yes for Men, No for Women
Digit Ratio: A Pointer to Fertility, Behavior and Health
2nd reason found to check woman's ring finger