from :donkey32.probaords.com - where they have a great discussion going on about rocket stoves.  I asked for recommendations for a simple emergency stove and this was the reply I received:

For a cookstove I would think a 5 gallon pail with a stove pipe elbow running through it filled with perlite or vermiculite(some use wood ash, but it tends to pack over time)would be more than enough for an emergency.

Some comments have recommended vermiculite over perlite even though it is more expensive.  It is lighter and might insulate better.

Here are a few instructional videos:

This first one is awesome, but you would have to have some serious welding/cutting skills.  It would be as heavy duty as the ones you buy I think.  I like the removable leg idea.




Here is another version - if free parts aren't available.  This is likely much lighter weight - would it last?



Something like what I was thinking... be sure to see notes below:



galvanized pipe gives off poison fumes at first.  Be sure to burn off without being near it - or better yet, use steel or black stove pipe.

Also - t joints rather than elbow might work better.

There was also some discussion that a place for the ash to drop to would be better and not tend to put out the flame -- that was the first I have heard about this problem or design.

#10 cans - LDS prepper has done a series of videos HERE