Except for the home windmill, TheSimpleDollar has some good suggestions on how to save money on such things as a programmable thermostat, commuting ideas, and power saving devices.
Digg.com posts: “If you need some good reasons to buy some neat gizmos, this guide provides solid arguments for the cost-saving attributes for a lot of different gadgets. Some of them are kind of boring, a few are way over the top (a home windmill?), but most of them are really neat ideas.”