Google Earth has been out for a while now, so I hesitate to post on it, since anyone who thinks it’s a cool idea has probably already heard about it. But it hasn’t been mentioned here yet, and this little treat today (make sure you zoom all the way in) seemed occasion enough.
People have also been using the software to look at large-scale impacts humans have had and continue to have on the environment, a la the UN atlas, only more interactive.