Oh, and if you want to boil a small quantity of water, the candle tin will work too.

Dick Smith Electronics 12V DC Portable Stove

There's no easily found link which goes direct to the (Australian) DS site, but Google that phrase and you will find lots of people trying to sell them... suspect that they are horribly inefficient and draw a massive 12V current... you will also find links on how to build your own too...

The cheap Chinese import canned butane gas stove are useful in a pinch (you need ventilation inside, or you will kill yourself!), but I exhausted a complete can trying to boil a few litres of water for tea...