This video from Microsoft shows off a prototype device that projects a screen onto a tabletop and then allows you to interact with it via motion sensing. Probably the best example of it's use in the video is they have one side of a chess board (the side you are playing) as physical objects and the other side as virtual. So the person you are playing against is displayed via the projection over the chess board.
This video features what appears to be a college student robot project. The difference here is that instead of a robot that walks around this robot takes a rubik cube and solves it. As far as I can tell they have one camera on each side of the cube so that the computer robot can analyze the state of the cube and then run a solve on it. While it is solving the cube there are also flashs of light so I'm not sure if they are camera flashs or LEDs. In any event it looks like the robot rubik cube solver solves the rubik cube in around 36 seconds. I assume that it works like computer run chess applications by running as many solving tests as possible until it gets a hit path that solves the cube.
Tactics Arena is a chess like strategy game except that each piece has a range. You can choose which and how many of each piece to set up on your side and then you must eliminate all the pieces of the opposing side. The game is pretty tough as well. It is multiplayer and uses a Java applet client. Games take a pretty good amount of time to complete. The graphics are nice and the view is from a 3rd person perspective. Suffice to say I lost most of the games I played.
This is an interesting puzzle game where you are running from a mummy on a chessboard. You move one square per turn and the mummy moves two squares per tern. You must trap the mummy to give you enough time to run out of the maze. Comes with an undu button so when you mess up and lose you can go back and correct your mistake. It may seem easy and first but it becomes more and more thought provoking the more you advance in the levels.