Read about Google Earth on Lifehacker. If you have a Mac or PC and a broadband Connection, Check it out.
FBOWEB.com has Flight tracking from a few airports such as JFK. Not sure this is a good idea or not, since it seems to show near real time tracking of airplanes heading towards JFK. I’m having fun plotting out where I and my family live. Seems to work ok with Web Proxies too.
On googleearthhacks.com you could download all sorts of overlays. There is even a good Google Earth Blog too.
Very cool and definitely worth checking out