Hungarian designer Levente Szabó has won the 2007 Electrolux Design Lab competition with his concept for the "E-wash," a washing machine that forgoes chemical detergent for "soap nuts," which are completely organic.
In India and Nepal, people have used the soap nut (sapindus mucorossi) for centuries to get their clothes clean. Szabó says that a kilogram of soap nuts would last the typical person a year, and soap nuts are good for people with allergies and gentle on clothes.
His design is attractive, but it's obviously the use of the soap nuts that sets it apart. And I wonder how difficult it would be to use the nuts with a regular washing machine most of us already use. From what I can tell from those selling soap nuts/soapberries, you can just stick them in a cotton bag and put them in the wash.
(Other winners of the competition can be seen here.)