Well, in fairness to him, that's not the main point of the talk. I mean, those first several minutes are mainly intended to show his personal path on the "bringing the real world into the digital realm" front, which is specifically *not* what he's talking about -- it's just there for contrast. The camera-and-projector system is the main focus, and that has nothing to do with that initial homebrew mouse-guts hand.

Admittedly, he hugely glosses over the camera-and-projector system as well: like I said, I think a lot of the demo is semi-rigged, in the sense of being highly optimized for very specific problems. But TED talks are limited to just a few minutes, and aren't *supposed* to be about the details -- they're all about the big idea. So I can't fault him for appropriately customizing to his audience...