Defense Grid: The Awakening is fantastic. 2008 was definitely the year of the tower defense games, at least for me. I played and enjoyed a ton of them, most notably PixelJunk Monsters, Desktop Tower Defense, several Warcraft III mods, and now as the coda to the list, Defense Grid. This is a commercial release you can pickup off of Steam and later this year on your Xbox360 via XBLA. It’s $20 for the PC and worth every penny. It distinguishes itself from the pack with excellent graphics and audio, a really well designed UI, great unit and tower balance, and a healthy dose of replayability. I’ve listed this as ‘finished’ because I’ve beaten every level now at the default difficulty level, but there’s a ton more to do, including replaying the levels at a higher difficulty level and medaling in each level. The developers have more planned for this game if it sells well, so please consider it if you like tower defense games – there are few better ones than this and it’s a bargain for what you get.