So you've heard of Kinect, right? It's the new xbox thingy that tracks your movements by having a camera pointed at you so that it can translate your flailing into on screen dancing and motion control.
If you look at a room with night vision goggles on, you can actaully see how it has blanketed the room in little points that it uses to map out the room.
Joystiq has a link to a video of what this looks like in action.