Design e2 is a new(ish) show on PBS that focuses on "The economies of being Environmentally Conscious". The show has a nice focus on Green Building and how architects can have a huge influence on our environment. I don't actually own a TV, so I haven't been able to see an episode yet, but they do have a video podcast with some exclusive content that I have enjoyed watching. Make sure you head on over to their website to view the trailer.
In case you didn't notice, that really is Brad Pitt doing some of the narrating.