Saw these on the 'net somewhere recently. It was an article about using a #10 steel food can (think tomato sauce at a pizza shop) as a stove, this was the heat source.
A tuna or cat food can (or similar), cut a strip of cardboard and roll it up to fit tightly in the can, then fill it with hot, melted parrafin wax. Use as a heat source for cooking or a candle. I'm sure they'd store well and last forever.