Keeper, the newest game from acclaimed adventure-game developers Double Fine and veteran designer Lee Petty, was revealed at the Xbox Games Showcase. As the name implies, the game involves a moving lighthouse--though whether you're playing and the lighthouse or a being managing it (a "keeper") isn't quite clear. A green bird appears frequently alongside the lighthouse, seeming to aid and guide the lighthouse as it travels through a variety of colorful environments including gemstone-adorned...