Ever wondered where the aircraft that is flying high above your home is heading for,well this site will show you many of the commercial flights in real time, though sometimes the destination accuracy is way off, but all the same for free is can be fun,let me know what you think, and if you install to google maps plugin then you can get a cockpit view, you will notice this tends to stop just before the plane lands
http://www.flightradar24.com/
http://www.flightradar24.com/