me_but_not on the subject of detecting virginity (from a thread in a post to _oral_sex_):
If the hymen is still intact, then she's definately a virgin...
If it looks like the entire first and second strings of the Green Bay Packers have been through there recently, she probably isn't.
This got the classic reaction from me; chuckling, pointing, and the normal cries of, "This is evil! Pure evil! Hehehehe..."