Water for Life
Back in 2005, Warren wrote about the elephant pump. A design from ancient China that is now being used in poor regions of Africa to bring drinking water to local populations, with the benefit that it can be easily assembled and maintained locally.
We found this Youtube video about it and thought it was really cool. Check it out, and if you like what you see, consider making a donation to Charity:Water (that's what Treehugger Founder Graham Hill wants for his birthday!) or to PumpAid.