http://www.earthbagbuilding.com/
Building with earthbags (sometimes called sandbags) is both old and new. Sandbags have long been used, particularly by the military, for creating strong, protective barriers, or for flood control. The same reasons that make them useful for these applications carry over to creating housing. Since the walls are so substantial, they resist all kinds of severe weather (or even bullets) and also stand up to natural calamities such as earthquakes and floods. They can be erected simply and quickly with readily available components, for very little money.
Earthbag building fills a unique niche in the quest for sustainable architecture. The bags can be filled with local, natural materials, which lowers the embodied energy commonly associated with the manufacture and transportation of building materials. The fill material is generally of mineral composition and is not subject to decomposition (even when damp), attractive to vermin, or burnable...in other word it is extremely durable. The fill material is generally completely non-toxic and will not offgas noxious fumes into the building.