3. Geometry Wars: Retro Evolved 2 (XBLA)
Weighing in at a whopping 40MB on XBLA, you won't believe the amount of joy this game can give you out of just a few floppy disks worth of content. You control a small ship that can fire in any direction, and the goal is to destroy as many shapes as possible without being touched by them; we've all played countless games like this before, right? However, you haven't seen a variation on the genre quite like this, namely in terms of its visual style, and also in its ability to make your heart skip a beat as you try to stay alive against dire odds. The variety of new modes introduced make this an effortlessly superior sequel to the first game, and though it's a massive shame that there's no online multiplayer offering, one can only hope that we might one day get a third game to remedy this title's single gripe. As a single player experience, though, it totally dazzles.