Thanks to rising heating costs, increased building costs, and a greater interest in eco-friendly living, the giant McMansion house is (thankfully) on the way out. Even people with money to spend are realizing nobody needs that much space, and you'll make less of a negative impact on the environment by living in something smaller.
Whether you're looking at pre-fab kits, tiny houses, or little cabins out on a remote parcel of land, there are plenty of resources for people looking to learn about the small housing movement. In fact, there's a whole Small House Society.
Visit their site for articles on everything from builders who support small house construction, to sherpa cabins, low-impact living. It's a great resource.