We somehow managed to guess 71% of the male and female subjects correctly in this test which asks you to determine which members of an online dating service are virgins are not, although we're not sure whether that has to do with our innate virgin spotting skills, the helpful tips provided (e.g., "People who don't look directly at the camera have something to hide" and "Virgins prefer shirts with collars"), or sheer luck. After all, most of them look perfectly normal otherwise.
The Virgin Game (okcupid.com - thanks Steve)
See also: The Gaydar Game (okcupid.com)
Previously: Artificial Hymens