i spent the last weekend at c-base
in berlin, germany attending a conference.
they had one standing around there that was bigger than MS's
i even played around with it for a a bit, here're some crappy pics i took: http://mein-bowl.de/mt/
nice thing: it was able to detect your hand or other materials responsive to infra red light
while they were still a good 15cm away from the surface and distinguish between touching the surface and just hovering over it
just take a look at the blue/greenish overlay blobs representing the detected area: http://mein-bowl.de/mt/dsc05394.jpg