Along the lines of energy efficient home, I have been looking at dome homes, earth homes, and spray concrete homes. I came across this web site. Pretty interesting story, well documented pics of the construction, and a long blog of the events since construction from the storms they have encountered.
http://www.domeofahome.com/index.html
http://www.domeofahome.com/gallery2/main.php
http://www.domeofahome.com/blog/index.php