If you don't have Java, here are some of the most popular satellites for tracking that you can view (no Java required!):  
Int'l Space Station
 
Shuttle
Hubble Space Telescope
Chandra X-Ray Observatory
NOAA 12
,
NOAA 14
,
NOAA 15
Click on craft
Change orbital data in lower right
Ctrl+Click on craft
Toggles on/off ground trace
Shift+Click on craft
Goes to web page about craft
Click+hold on map
Display first visible at longitude