Playpumps International, a South Africa–U.S. nonprofit, builds drinking-water wells in impoverished parts of Africa that are pumped by children playing on fun, colorful merry-go-rounds. Clean water, fun, and exercise—Pruned thinks it's such a winning idea it should migrate to the obese Southwestern United States. You always see these kids in Sally Struthers public service ads just lying around, so somebody finally decided to put them to work. And if you want more water, you can just grow more kids. I guess children really are Africa's most valuable resource.