I was thinking just the other day how flying helos in Desert Combat was the most difficult thing I've ever done in a video game and how satisfying it was when I mastered it. Then we went on to things like Katana and I playing follow-the-leader flying through city streets below rooftop-level at top speed with each guy trying to shake the other.
And thinking of maps like Oil Rig, and launching SCUDS, and the havoc we wreaked with the AC-130 gunship...
Totally fu*king awesome.
Hands down, DC for me is the greatest game ever created. There has to be a core of die hards out there still playing it.