Thanks for the info bacpacjac.

I had suggested pop can alcohol stoves as a fun activity to one of the Scout leaders and after seeing this thread again was wondering if I had given some bad advice. For risk, I'd tend to think they aren't much more risky than the white gas stoves they use camping, but I'll let those guys do their own risk assessment if they decide to try it - just wanted to ensure I didn't suggest something blatantly disallowed .

I also like the idea of hobo stoves designed to run off of a wood fire. My primary hesitation about them is the Alberta's Provincial Parks have regulations in place banning the use of dead wood for fires which really sort of defeats the purpose of a wood burning stove for a fair bit of the camping they might do, either with Scouts or especially on their own with their families (there are areas they could be used though).

On a side note, I seem to recall making a tuna can stove like that when I was a kid; they seem like they'd be good for an emergency kit. We also made smaller rolls of cardboard tied with string and dipped in wax as fire-starters.