I came across one at
www.atcsimulator.com (I think! Try some variations on that if it doesn't work) It looks quite tasty and has some moving graphic examples on the web site. Can be voice controlled too!
I used to have Tower but have no idea where the software diappeared to. If you come across a web site with it, perhaps you would be good enough to let me know as it is quite entertaining as previously stated.
Cheers:
