PCPro has posted a video of this awesome SecondLight demo at PDC 2008. SecondLight works by projecting two different images from beneath the table. The table surface itself is formed of a liquid crystal display that switches between frosted and transparent states when electrical voltage is passed through it. By rapidly flicking the screen between the two states, the table appears as permanently diffuse, displaying an image like an ordinary Surface table. The screen is, in fact, transparent for half the time. And during these periods then second image is beamed on to the paper, confusing the eye into believing it's seeing two images simultaneously. Using an infrared camera, the secondary "display" can also be used as a multitouch surface. What's more, it can display video.