Recent visitors to the National Mall in Washington, D.C., might have wondered if they accidentally stumbled upon a mobile-home park of the future. Starting October 1, 20 eccentric-looking, solar-powered homes sprung up for the 2009 U.S. Department of Energy Solar Decathlon, a student competition to design and build livable, energy-efficient homes. Twenty integrated-discipline teams from around the world were involved in this year's contest. Team Germany was named the overall winner. Click on the slide show icon to see images of the houses.