I made this rotating galaxy-type thing as an experiment with actionscript. Obviously looks better with more stars, but it slows down if you have a lot. If you have a SERIOUSLY fast PC, try 500 in the centre and 1000 on the outside. Otherwise, stick to about 750 total. You can put more but it'll be slow and jerky. Type in the values you want and press the white button to start. You have to refresh to do it again.
Added an option for smaller stars. I think they look nicer.