The Rural Studio is an amazing project.  A friend of mine went on a service trip with high school students to work with these folks and was telling me all about it a few weeks ago.  I was instantly psyched because this combines my interests in recycling and design/build. From their website:

"The Rural Studio, conceived as a strategy to improve the living conditions in rural Alabama while imparting practical experience to architecture students, completed its first project in 1994. 

"The Rural Studio is a design-build architecture program run by Auburn University which aims to teach students about the social responsibilities of the profession of architecture while also providing safe, well-constructed and inspirational homes and buildings for poor communities in rural west Alabama

Check out some of my favorite designs. 

The butterfly house

This one incorporates reused windshields

My friend worked on the last house which is made of carpet.

Then the other day I saw this new project by the  where they are working to design an easily replicable housing plan where the materials and labor cost under $20K aptly named 20K House.  Check it out here.  The designs aren't as adventurous or modern as their other work but still simply beautiful.