The founder of the now-global “Flash Mob” movement, in which seemingly random groups of people appear at a designated location and do something odd for a few minutes before dissipating, has decided to end his New York City-based mob’s performances. The founder, known as “Bill,” organized one final flash mob which was supposed to eventually lead participants to a party celebrating their common love of befuddling the public. But instead, the mob was thrown for a loop by a single man with a briefcase and a neon sign, and participants wound up as puzzled as the passersby they were supposed to be confounding. Naturally, Bill thinks the whole thing was just great.