One of the projects drawing a big crowd at Microsoft Research TechFest event in Redmond today was LucidTouch, which lets people control a portable touch-screen device by placing their fingers on the back of the case. A camera sees where the hands are positioned and renders a shadowy image of them on the display. Here's a video of Microsoft Research's Patrick Baudisch showing me how it works.
Source:→ Todd Bishop's Microsoft Blog
Microsoft, Microsoft Research, TechFest, Hardware, LucidTouch, Video