How walkable is your neighbourhood? The more you can walk somewhere, the less you have to drive so it makes sense that a community structured for walking would help to reduce greenhouse gas emissions. A new Google maps mashup can called Walk score can give your community a "walkability" rating based on the distance to walkable locations near your address. An interesting concept with a side benefit of finding nearby shops and restaurants that you were not aware of, but it did list some locations that were 40 miles away. We don't know about you, but 40 miles is not really considered walking distance to us.
What does your house score?