This is a lot of fun. I've always been a huge fan of flight sims, but I never realized that ATC was just as much fun. Just a few notes:

* All the planes enter at 90 degree angles. I assume this is intentional, but it would be nice to have semi-random entry angles.

* There are a fixed number of planes in the simulation. It would be more challenging and fun if more planes would arrive while I'm taking care of the others.

* The words are small and hard to read.

All in all I think this is a really cool simulation. I can see myself wasting many more hours on it. Thanks!