This is the portable stove I use; a Trangia burning liquid fuel. The fuel in the picture is about 87% ethanol; a fuel with higher ethanol concentration would burn with a hotter flame, but the one I'm using is half the price =) Now, I don't remember where I got the trangia from. I'm pretty sure I didn't buy it, but just got it from my parents long long time ago, when they bought new gear - or something, that has been the years of a lot more severe depression which impaired both my short and long term memory. Also, I had two full trangia sets, so I gave the other one to a friend who had none. If I had a lot of time to tinker with self-sufficiency stuff, it would be super interesting to look into ways of producing my own fuel; maybe moonshine or bio-gas?