At our work, we have an expensive and temperamental touchscreen whiteboard. It is a pain to work with, and cost us a bunch of money when it was bought (probably seven years ago or so).
So
this usage of a Wiimote seems really cool to me. It does the same thing, but projected onto any surface, not just onto a touchscreen. And for a whole lot cheaper: a Wiimote, an LED light and some wiring and that is pretty much it. It's a pretty cool video.