PSP games.

If you like turn based strategy games, get Disgaea. It'll last you...god...SO many hours. The gameplay is pretty deep and interesting, although the random dungeons inside items can be a bit awkward at times (make sure you always have a ranged attacker, sometimes enemies spawn on platforms absurdly far away from you), the humor is lighthearted and fun, and it's all in all a great game. I'm actually thinking of buying a new PSP (old one got sat on, screen broke) just to play it again.