Ed, I call him Ed, like we're friends or something. Anyway, Ed has all kinds of great little tips in his book, Living Like Ed. At first I thought this book might be above my commitment level because he's hard core, but it isn't. There's something anyone and everyone can do, many things that is. There will be plenty more posts to come from this book. I only have a minute though so this will have to do for now.
I should mention, this would make a great gift for your green loving friends.