I just bought Armadillo Run last night and am really enjoying it. It is a physics simulation game and, while that might not sound like much fun, it really ends up being a very cool puzzle game. Your aim is to guide a ball-shaped “armadillo” through a pathway you build from various materials such as metal tubing, rope, cloth, elastic bands, etc. Once you’ve completed building your structures you turn on the simulation to see the physics go into action. Seriously, it’s better than I’m making it sound. There is a free demo that has tutorials and introductory levels included. For the time being it’s Windows only.