Solar - The sun is free and in most parts of the world, you can get all or at least part of your power needs from solar.
Build it Solar has tons of info and plans on all types of systems
Photovolatic - Our 4.5 Kw system cost $23,000 before the tax credit and gives us around $150 worth of electricity per month. Not only did the system add 10-20% to the value of our home (more than the cost of the system itself), but it will pay itself off in about 12 years, then continue to give us free energy for years to come. There are often panels available on ebay, or you can purchase parts from various internet suppliers and install it yourself, but if you want to take advantage of the rebates and tax incentives, professional installers may save tons of time and paperwork.
AZ solar - A family run site with great information on alternative energy
Solar Water Heating - A few panels can preheat your home's water so that with a little more juice from an electric on-demand heater, you'll have efficient, low-cost hot water.
Solar Air Heating - Commercially made panels can be purchased, but this is a DIYourselfer's dream! Here's an innovative home design and another featured on instructables here.
Wind - Rooftop or small tower wind generators can easily power your home or even a cul-de-sac!
Hydroelectric - Modern microhydro generators can be placed in a stream and make continuous power without dams or significant diversions of flow.
Green Energy Credits - If you can't make your own energy, you can purchase energy credits which offset your energy use. Although your power isn't directly coming from renewable sources, it's renewable "by proxy"
