I loved the in-game radio and the enormous number of goofy/awful commercials. It was a huge amount of fun to build a city in SC2K or SCURK, fly through it running missions, and then burn it to the ground with an Apache "fighting crime" (aka clearing traffic jams the easy way).

The thing I remember most about that game is dropping wounded passengers because my heli couldn't keep the load up in a storm :-)