Google Earth is pretty freaking cool. There's other places to get satellite imagery but Google Earth wraps it into a package that has pretty much endless possibilities. I downloaded it last weekend just to see what all the fuss was about, and realized that I could use it to measure distances. A bunch of us from work swim one night a week in Lake Washington and we've always had to guess the distances between two docks that we do laps between at about 50y. I fired up Google Earth, found some football...