A multi-fuel, light weight, almost FREE stove that you can make with material found in almost every house. Great for hiking/camping and emergencies. (great project for anyone, but especially to do it with your kids). Watch this great video to learn a very useful skill. After all, is your skills and your ability that will keep you alive in a SHTF scenario.
I also recommend this video for a nice energy generator, using any kind of organic material this generator creates energy, even from dead leaves