MIT (Massachusetts Institute of Technology) students have put together this contraption for developing countries that don’t have reliable (or any) access to electricity to help them efficiently wash their clothes without polluting the lakes or streams they typically use.  They claim it can be built locally, which will create jobs, and the end result helps the people save time, too.
An earlier version of this design won first prize at an MIT IDEAS competition in 2005, and the design has been steadily improved to be lighter, more durable and easier to ship.  Read the full story here.