Link for those who missed the Ammo Rocket Stove article:
http://www.bearridgetradingpost.com/2011/07/ammo-can-rocket-stove/
Looks like, in order to add the "mass heater" functionality, you need a chamber (ie, a metal barrel) around the updraft chimney. Then you channel the exhaust through your mass to be heated (gravel bed, adobe, etc), then exhaust it outside.
From my understanding, the exhaust temperature tends to be really low.
Hmmmmm, I prefer other ways of cooking. However the heater version looks interesting and I may have to research further
http://www.richsoil.com/rocket-stove-mass-heater.jsp
Please also add me to your ping list.
Please add me to your list