The NY Daily News reports of an interesting little sign alteration at Union Square. It seems that Harry Potter fans have added a new train line—the 9 3/4 train. This number is a reference to the platform in the Potter books where one can catch the train to the Hogwarts School Witchcraft and Wizardry.
The sticker is placed in the spot once held by the defunct W train. The MTA says they had nothing to do with it, but it would surprise me one bit if one day they stooped to the level of selling ad space on their signage.