My favorite RE discussion groups

There are a number of good discussion groups for renewable energy topics. The following are some of my favorites, feel free to leave comments on yours and I'll update the list.

Green Trust Renewable Energy
3rd World Energy
Appropriate Community
Backwoods Home Magazine
Electric Transportation
Renewable Energy
Homemade HAHSA Wood Heaters
Human Powered Machines
Log Home Talk
Rain Water Harvesting
12vdc Powered Systems
Biodiesel Basics
Biodiesel
Babington Burners
Simply Off-Grid
sKOOLie Conversions
Waste Watts
Lister / Listeroid Diesels