Straight from the “How we should really be using our brains” files, comes this story about the guy who built the segway (if you have no idea what that is, have a look at the site: they are an astounding piece of engineering, but are equally a spectacularly frivolous toy in almost all applications) who has designed a 1kilowatt power plant and a ~1000L/day water purifier system that work by burning cow dung (or for that matter, just about anything you can find that you can set fire to…).
The notion is that if they can get the price of production down, and put one or two in each small african and asian village, then the villagers will have clean water (which in effect = no water borne illness, which = decreased illness, increased productivity, and better lives) and power for small applications (like a community refrigerator, or a light bulb in each house (which will allow them to spend evenings in recreation, education, or further productivity)).
For all the brilliance and creativity of our modern science and engineering, there are far too few of these ideas being developed as far as I can tell, and so we must loudly aplaud this guy for his genius and his social responsibility.