This might be a pathetic thing to admit, but I sometimes think of things that I must do in real life along the lines of achievements in World of Warcraft. It’s a way of motivating myself to get them done. Indeed, sometimes this is pushed to such a nerdy limit that I wish that there were a to-do list interface (I actually use Remember the Milk) that somewhat mimicked the achievement screen in WoW.
http://xkcd.com/189/