A team of researchers at Stanford University are living the dream: they've used Kinect and a robot arm not to cure disease or solve the energy crisis, but to build something for lightsaber practice.
The Kinect camera is able to track the movement and placement of a human opponent, with the arm programmed to respond accordingly. If a swing is blocked, then the robot pulls back and initiates a new move. Which it will presumably continue to do until it ceases to function or you are dead.
Or...walk away from it.
While the feat is impressive given the technology used, it is a little slow. If you rip the video and play it back at twice the speed, it's a lot better. Especially if you make lots of "whoooosh" and "wwhhrrrrrr" noises, with a "NO THAT'S NOT TRUE THAT'S IMPOSSIBLE" thrown in for good measure.