In 2005, Microsoft made a "Jump In" ad for their Xbox 360 console that never aired. The ad, deemed too controversial, showed commuters on a subway platform playing "shoot 'em up" with their fingers (Bang!).
Like many viral things, the ad has recently gone 'round the web again, so here it is for all of you who haven't seen it: Hit play or go to Link [YouTube]
And if you like that, check out the casting call for the banned Xbox 360 shoot out ad (which is actually better than the actual ad!):