I don't know if this is a great idea or an invitation to clog up your Twitter feed with inanity (go ahead, hit me with your best shot in the comments on that open invitation), but Tweet Defense
takes the usual tower defense game to a new "social" level by upgrading your towers based on how much you tweet. What's the worst that could happen, right? Slidetoplay says
it'll debut at $.99, but what price could you put on leveling up via Twitter, really?"