The PROBLEM - No electricity in the village. Cannot afford a diesel generator. Then how to get groundwater in a tank overhead so that water can be made available though pipes and taps around the village.
The SOLUTION - A toy for children. Yes a merry go round wheel. Children are endless bundles of energy as they play on for hours. But underneath this wheel draws ground water and pumps it in a tank overhead (seen in the background). The groundwater drawing works much like our common Indian hand pumps.
The picture below depict the working of this pump.
Source : http://www.waterforpeople.org/extras/playpumps/how-playpumps-works.html
This technology is being implemented by "Water for People" in African Nations on charity basis and has been developed by PlayPumps International-US.