Haier's Wash2o doesn't use detergent, but instead breaks down the water into ions that then bond with the stains, dirt, and funk. (Someting about breaking the water down into OH- and H+ ions...without getting into all the chemistry behind it.)
We like the idea of not using detergent, but it may be awhile until the technology hits the US. The Wash2o will be available soon in France and cost around 700 euro. Until then, if you're looking for a greener alternative, you may have to stick to making your own earth-friendly detergent.