To this day I still play the first Halo multiplayer on PC. Off and on since I guess 2003 when it came out.
I just played it for the first time in a while and a whole bunch of memories came flooding back. My "peak year" was 2011, where I logged in daily and made lasting friendships.
I thought it was gonna be over when GameSpy stopped running the servers but further patches have been released so the community can still keep playing. At any given hour there's only about 30 people playing, so the community is small but dedicated. It has a nice small group feel like EoFF, but with more rotating names.
Also, this was the only game I played where I heavily used Xfire before that service shut down, as well. I miss that website.
What old multiplayer games do you still play, and how big is the audience? Or what game would you play had the servers not shut down?