The military, for years, has built structures with blocks of foam. They are glued together and covered with some kind of material. I am not military but I have seen them at Fort Polk.

Many years ago I read an article about a company named Amhome (I have no association with the company). If you are looking to build an energy efficient home this method of construction might be of interest. The foam blocks are glued/joined to build the "form" where cement is poured. I searched for the company and ran accross this article: http://www.homeenergy.org/archive/hem.dis.anl.gov/eehem/98/980712.html