For several months I have been closely following development of diy multi-touch displays on the internet. A few weeks ago I decided not to spend the $15,000 for the Microsoft Surface and build my own. From months of lurking on the Natural User Interface Forums, I decided to use the Laser Light Pane method of illumination with infrared lasers aimed just above acrylic surface. As you can see from the video on the right, the results were fantastic. Here are some build notes (see photo captions for more info):