In retrospect, building houses with high R values, as well as appropriating fuel efficient transportation would initially cost more, but save an arm and a leg in heating/cooling costs down the road, as well as tons of carbon dioxide. What I thought was really interesting was the use of evaporative cooling in rammed eath/etc construction, since it requires the cooler air to be draw in on one end, and push the hotter air out of the other end, reminds me of the whole Qi idea.