When I saw a version of this image, in blue and green colored lights (and with a strategically placed ??ensored?sign—image may not be entirely safe for work), on a billboard at night in lower Manhattan, I thought it was about the coolest ad I’d ever seen.

When a bunch of them turn up in random locations in Boston, it practically shuts the city down.

UPDATE 2/1: Link fixed; Gothamist cites media reports that randomly placed LED devices bearing that image also removed from various New York locations.