Well all of you actually :)
Check out this link http://thermalcooker.wordpress.com/category/thermal-cookers/wonderbox/ (the photo above is from there...obviously the quality is better on the actual website)
My mom made us each one last year and although I have yet to use it, I'm sooo intrigued and impressed by the idea. I have heard them called *wonder boxes* or *heat boxes* and there are probably many others out there.
Basically the idea is this - heat water (over a candle) to boiling, add your ingredients. Place lid on and put in center of the wonder box. And let it sit - 5 hours and your food is done! (depends on what you make...check the link out for recipes and such). It cooks anything and everything and is a great way to save energy, cook great meals with less mess and fuss (like while camping), or in my cousin, Krystal's case - a great way to cook great meals without needing a stove or oven and without heating the house/kitchen on a hot day. You can also use them to keep dishes warm - my aunt brought her to easter dinner to keep the potatoes warm. It was brilliant!!
So enjoy - what a fab idea I think. I need to try mine out one of these days - don't worry, I'll blog about it :D