The Wave House (aka 'La Maison-Vague' in French) was designed by French designer Patrick Nadeau and features an entire exterior made from grass and various green plantation. The Wave House is actually beneficial to the owner as well as the environment, as the external green walls act as thermal insulation, making heating costs significantly lower in the winter time and making the inside cooler in the summer.
The Wave House looks a bit like a hobbit cave, but I think the design just adds to its unique and sustainable feel. It's a pretty smart idea -- especially since it's designed as affordable housing.
