I played Mechwarrior 4 way too long. Almost 7 years between the Microsoft Gaming Zone, and then server play. In fact, I gave up MW only when my clan switched to Guild Wars. Now I don't even have a desktop, but I'll buy one if this new game is good.
For a long time, there were MW mu*'s out there, with a pretty neat combat system, very true to the board games. Maybe there's one or two still around.