Temperatures in the low twenties yesterday afternoon did little to dissuade thousands of people from entering the subway at stations across NYC and promptly taking off their pants.

The occasion, of course, was Improv Everywhere's No Pants Subway Ride, which launched its half-naked hordes from 10 different locations throughout Manhattan, Brooklyn, and Queens, and wound up with a huge butt-shaking party in Union Square.

Charlie Todd and his Improv Everywhere crew started No Pants sixteen years ago as a seven-person prank, and though it has grown to epic, widely-publicized, and even international proportions, there remains a good number of our citizenry who are generally surprised (and usually delighted) to encounter pants-free people riding the train.