I meant to put this together two months ago and am finally getting around to doing it.
I went to a workshop where we played with fire for two days. There were several instructors and the primary instructor is the author of
Rocket Mass Heaters: Superefficient Woodstoves YOU Can Build.
While I was there, it was clear that this guy had built an awful lot of these. There were several right on the property. I was able to capture most of them in the video mode on my crappy camera.
And now, here is my collection of video bits ...
http://www.youtube.com/watch?v=LfKHVoCY2so