Stfrn or Uyaem.. can't decide.
Both pretty good, this guy Kerol was also pretty neat however
I would have to say Rennaj was the all time coolest most knowledgeable and helpful, and yep fun
At least you probably spent the most time online
Darn, I need a list of old GMs. I remember this very cool GM who got inspired by
gm-dave at some point and wrote some great stories about his experiences. Can't remember his name :/
edit:
OMG, found the cool GM's name by searching through piles of old forum posts: Syilph. Active before 2007.
His coolness can be illustrated by his avatar:
.
The avatar was of course made by Karyuu. Which reminds me: Karyuu was cool!
And not to forget: Akaye.