The first DVD, "Fire Science", gives the background information needed for rocket stoves and rocket mass heaters. The second DVD is "Sneaky Heat" referring to rocket mass heaters. The third DVD, "Boom Squish" is about rocket hot water and the last DVD, "Hot Rocket" is about rocket stoves, fox stoves, pocket rockets, and a rocket forge.
The leading innovators today on rocket mass heaters are Ernie and Erica Wisner. They have built over 700 rocket mass heaters and their recent designs are superior to the designs of systems five to ten years ago. They are the moderators for the wood burning stoves forum. These are their recent designs:
6 inch rocket mass heater plans $20 for a 13 meg PDF of detailed plans and instructions
Ernie and Erica's book "Art of Fire" goes into detail on all sorts of fire based inventions, and heaps of things most people never knew about fire. It covers the foundations of rocket mass heaters and the predecessor, the rocket stove. And the predecessor to that: the fox stove. Rumford fireplaces, pocket rockets, masonry heaters, brick ovens, cob ovens, earth ovens, ox cookers and on and on and on ...
Although a lot has happened since this book was written, this book still has a lot of good information. It has explanations on how this type of wood burning stove works in general. Rocket Mass Heater Book
A rocket stove is the predecessor to the rocket mass heater and is designed for cooking food. They are for outdoor use only, although folks in some third world countries use them indoors because they are so much cleaner and more efficient than what they used before.
A lot of commercial rocket stoves are starting to come onto the market and they all seem to be missing parts that seem pretty essential to me. And then I heard about the kelly kettle - this seems to be an actual innovative improvement over all the others: the kelly kettle The idea is that the water sits inside the heat riser. I've seen these in use, and they boil water very fast with just a couple of twigs.
To better understand the rumford, you should first consider the traditional fireplace (aka "the oxbow cooker") which is designed to get heat to go outside so you don't get too hot while cooking on the fire.
The rumford fireplace design is to maximize the radiant heat going into the room.
Thanks to Erica Wisner for use of these images. She has a massive page on this topic called fire science.