The fart joke is one of the mighty pillars of comedy because it's so basic. Any embarrassing action accompanied by a sound effect is automatically rendered hilarious to all witnesses. And although good timing can amplify the effect, it's a joke that doesn't usually require any setup whatsoever. It just happens and it's funny.
Unless you're the gang at Casual Brothers, who decided that their fart-joke-cum-action-game Orcs Attack needed a bit of exposition. In this four-player co-op brawler coming to Xbox Live Arcade, PlayStation Network, PC and OnLive late in 2012, orcs driven out of their homes by ecologically-challenged humans have developed dangerously explosive flatulence due to consuming fruits grown in their now poisonous environment. Now they're turning the tables and using this new found anal armament to seek vengeance.
Looks silly, fun and very promising for a game with up to nearly a year remaining until release. Hell, the above video is footage from a demo level from E3 of last year, meaning things may have yet progressed quite significantly already in the last six months. Worth keeping an eye on, I'd say.