Our first choice is straw bale construction. Second is earth sheltered. (when we get debt paid 100% and can pay up-front for a home)
I think they are beautiful (straw bale) and the church that our newly forming church "borrows" every once in a while is also straw bale...but nothin' fancy since the members built it themselves.
Love the alternative building and basically any home that goes against the "McMansion" craze.
Michelle