This one ranks right up there with Dead or Alive 4's "Five Straight Losses" achievement (worth zero points, natch). Gastronaut, the studio behind the upcoming XBLA game, Small Arms, have created the first viral achievement. Four of Gastronaut's employees will start being the only ones with the achievement. Anybody who plays against one of these four will get the achievement. In turn, anybody who plays against those people will get the achievement and so on and so forth until the whole world is...er...infected with success. Pretty neat idea if you ask me. Which I'm pretty sure you did.
If you're not familiar with Small Arms, it looks an awful lot like Smash Brothers for the Gamecube, except with guns. Lets hope it's at least half as fun.[Via 1UP]