Kid-powered: According to BoingBoing, the Colombian sustainability village Gaviotas features a pre-school that has a see-saw disguised as a water pump. Gaviotas, energy independent since 1995, has also made a slew of innovative tools and toys, from a wind-powered musical organ to a solar oven:

• a high pressure solar cooker
• methane burners
• hot-water solar panels
• parabolic solar grain driers
• self-cooling rooftops
• cooling wind corridors
• corkscrewing manual well digger
• variety of highly efficient and durable windmills
• specialized bicycle for the Llanos
• pedal powered cassava grinder (10 hours work done in 1 hour)
• rotating drum peanut sheller
• ox-drawn land graders
• one-handed sugarcane press