One of my personal interests has long been ways to reduce my impact on the environment. I grew up in a home with a mother who was an avid environmentalist long before it became cool to be one. As a Realtor, I'm particularly interested in green homes and just found this great link that you may want to visit if it's something that interests you as well:
http://realtytimes.com/rtcpages/20070405_greenpaymore.htm
When you get to that site, there are other links to more Green Home information too.