My first encounter with Earthships was by accident. I was driving through the New Mexican desert, on my way to Taos. Off in the distance I could see some strange buildings and I said to the two ladies with me "What are those odd structures — those unusually shaped buildings — what could they possibly be?" Little did I know they were Earthships — houses designed to be self-sustaining as possible. They are usually made of concrete blocks, aluminum cans and used tires packed together with rammed earth. They also usually make use of solar power, passive heating, thermal mass and greywater recycling for indoors gardens. All very innovative, great stuff. Earthships also tend to be very vernacular or even, shall we say "eccentric", in their design. But the next time I'm in New Mexico I'll rent one for the night. :: Earthships (thanks to Lloyd for the tip).