It is a bit impressive, isn't it?
But when you think it had to get up to around 18,000 mph to escape the earth's gravitational
pull, to achieve orbit, and the earth is around 24,000 miles in circumference, it all makes sense.
renrut: That n2yo site is pretty good.
Here's another one I use on occasion (try the zoom buttons) for ISS tracking....
http://spaceflight.nasa.gov/realdata/tracking/
and this one has many satellite options as well, but no ISS tracking anymore(it's related to the preceeding one)....
http://science.nasa.gov/realtime/jtrack/
and another one I found today with ISS tracking....
http://heavens-above.com/