I've been an active gamer since the late 70s, and a Game Master of various games for almost as long. I've run various games at GenCon (Indy and back when it was in Milwaukee) and been part of the Call of Cthulhu Master's Tournament at that con.
I have done some writing for Chaosium (the publishers of Call of Cthulhu), and I helped edit an early edition of their Cthulhu Dark Ages rules. I headed up their first Cthulhu Dark Ages Master's Tournament (which was a blast).
I am familiar with TONS of role-playing games, but those I am most familiar with are as follows:
AD&D / D&D (Any edition, up to 5e)
Call of Cthulhu
Call of Cthulhu Dark Ages
Call of Cthulhu Down Darker Trails (Old West setting)
Traveller (name the edition, I've probably run it)
Pendragon (Adventures in King Arthur's time)
CyperPunk (again, multiple editions)
Shadowrun (ditto)
World of Darkness (2nd Ed. is my favorite)
Vampire The Masquerade
Werewolf, etc.
And a plethora of other weird and wonderful games...
I am also in the midst of constructing a game of my own creation specifically for gameplay on Roll20.