In order of how long I've played:
Battletech (12ish years)
D&D 2e, 3e, 3.5e (9ish years between all the editions)
Pathfinder (Loooooveeee iiiiit) (recent)
D20 Modern zombie thing. I don't actually know. I think the DM kitbashed a bunch of things? (only one campaign)
Just going to start SR in the next couple of weeks. I've done a session or two in all sorts of things (Deadlands, Savage Worlds, Octane...) that I just didn't click with, always wanted to play Vampire and Changeling but can't seem to find a real group for it.