Leave the car keys on the hook by the door and walk to your destination: it hardly seems revolutionary, but that simple act can be the greenest thing you do all day. The trouble is that for some of us, there's little choice but to drive. The grocery store, park, or library is just too far away. It's enough to make you want to move. But before you do, check out Walk Score. Type in your address and the site gives a score from 1-100 and shows a map marked with all the places you might go. Among other things, the site points out that choosing to live in a walkable neighborhood may result in: • Better health, • Stronger local businesses, and • Reduced carbon emissions. For fun, you can check out some celebrities' houses, like the working ranch in Crawford, Texas, or Bill Gates' house. We ended up with a 75, but AT's headquarters scored an almost-perfect 98... so, AT, how walkable is your (dream) home?