Check out University of British Columbia's Video demos.
Here are a few stills and videos we've collected:
Alex Birdwell and Michael Peshkin describe the lightboard setup
Draw and talk electronics, 4 x 8 foot board. (Michael Peshkin)
Draw and talk physics, 2.5 x 5 foot board. (Matt Anderson / SDSU)
Add hand-written text to a powerpoint slide, as you talk
Use matlab to create a moving graph