The finger moustache virus
Andrew sends us this video. The local TV element is hysterical, but what I commend you to is the extremely viral nature of the tattoo. By turning something passive (body art) into something active, the item spread like wildfire. (It also helps that it feels like a much smaller commitment than say, an eagle on your back.)
Of course, lots of people are taking credit for inventing this. My guess is that it goes back to the days of particularly silly pirates.