N. Rain Noe reports  from the AU conferecne via Core 77:

A company called Infinite Z was demonstrating their Z-Space display platform, a 24-inch monitor laid nearly flat on a table. You put on a special pair of glasses--no bulky headset, they're like a super-light pair of spectacles--and the display turns into a freaking holodeck.

3D objects appear to be perched on top of the screen. Using a light pen, you can grab objects, pick them up, flip them over with millimeter precision--it's like you have the object skewered on a long laser beam, and as quick as your hand turns over, the object turns over at the same speed. You can't see any rendering happening, it's like you're holding the real thing.

Dynamic use of stylus/touchpad combination to render and manipulate CAD objects! While they only show a small array of what's possible, the inference is pretty amazing. Take a look at this video: