The video takes awhile to download, but it's worth it.
From their web page:
Since refining the FTIR (frustrated total internal reflection) sensing technique, we've been experimenting with a wide variety of application scenarios and interaction modalities that utilize multi-touch input information. These go far beyond the "poking" actions you get with a typical touchscreen, or the gross gesturing found in video-based interactive interfaces. It is a rich area for research, and we are extremely excited by its potential for advances in efficiency, usability, and intuitiveness. It's also just so much fun!
Our technique is force-sensitive, and provides unprecedented resolution and scalability, allowing us to create sophisticated multi-point widgets for applications large enough to accommodate both hands and multiple users.
The drafting table style implementation shown here measures 36"x27", is rear-projected, and has a sensing resolution of better than 0.1" at 50Hz. Stroke event information is sent to applications using the lightweight OSC protocol over UDP.