This couple is having last minute thoughts about joining the MTA's new underground fetish club. (Photo by Spider Jerusalem)

All aboard the Bondage, Discipline, Sadism, and Masochism trains! You know, assuming that is what this prankster meant by replacing the "F" stickers in the Broadway Lafayette subway station with "S" stickers.

It's actually sort of fitting if you look at the powerless straphangers as the submissives in the situation, being dominated on a daily basis by the all-powerful MTA, and each MetroCard purchase being a signed, formal agreement of a complete and total power exchange. If that analogy is too dark for you, don't worry—the safe word is Alfred Ely Beach.