This one sounds like an harassment tool, but it's really not. I got this idea on one of those evenings when you look around and simply ask yourself: "Where are all the women?!" - Quite frankly, little is known about the migration routes of males and females in our societies. We take it for granted that men and women show up in bars and restaurants in certain times of the day, but if they don't, we have no clue what has happened or where they are (unless there's a Ricky Martin concert round...