ThinSight is a IR emitting and detecting layer to be placed behind a display such as a LCD. It has exciting possibilities of enhancing multitouch technology and interactions.
The device relies on a two dimensional grid that emits and receives infrared light. Because the light is IR, it does not interfere with what is being displayed on the LCD screen. It's multitouch properties derive from its ability to create an image of what is in front of the screen. If your hand is in front of the screen, it will reflect the IR being emitted, and the device will received it, resulting in an image of your hand on the screen.
Actual touching not needed to interact with the device, as it can calculate the distance an object is from it, and it can also detect how much pressure a finger is placing on the screen, as the finger will cover more area and increase in size on the image as more pressure is applied.
Another exciting ability this technology provides is being able to interact with other IR devices, such as sending and receiving data to PDAs or cell phones, it can detect the IR codes emitted from the devices, and respond by emitting codes back to the device. It also can communicate with more than one device because it can "see" where the device is and send IR beams only to that place.
I think ThinSight is an amazing technology that if fully developed, could revolutionize the way people interact with computers. It may be weird to know that your computer can "see" you, but I think the possibilities are too great not to explore this technology more fully.