When I’m camping, I much rather build a fire than fuss with a camping stove. A campfire becomes a center for the evening, while a stove is efficient by nature and doesn’t provide much of a hearth. Still, there are places where wood is scarce (wood-gathering is illegal in many state and national parks), and a lightweight stove is essential for many backpacking trips.
All a camping stove really needs to do is burn some kind of inexpensive fuel to heat a grill, a pot of water, or a frying pan. Punching careful holes in an empty can makes a perfectly functional stove that can burn all kinds of cheap fuels like mineral spirits (available at every hardware store in the country). I made the stove pictured here from a pair of aluminum cans. It actually burns so hot that can melt cheap aluminum grills; it left permanent dips in my backpacking grid after I let it cook a little too long. How’s that for do-it-yourself value?
My stove mostly followed this model, which combines aspects of the models described here and here. I left it unsanded and unpainted, so you can really see the seams where the parts come together. The flattened can top acts as a simmer ring; when it is placed atop the stove, it cuts off most of the jets while letting a limited flame come through the hole. You can also just build a second stove with fewer holes to use only for simmering. The stoves are so lightweight and cheap to make that having two of them isn’t a big deal.
If I were to make a new one today, I think I would follow the Super Cat design, which is so simple that it cannot fail. There is also a variation known as the Simmer Cat that would suffice for slower-cooking recipes.