I have times where I play more then at other times.
I played War Birds as much as I could afford for wuite a while. That was such a good game till they messed it up going to ver 2.0.
Ive liked Tac Ops a whole bunch in the past, again until they messed it up.
Day of Defeat is a great game and my go to game here for quite a while now. One of the few that only got better comming out of beta versions into a full independent version. $20 spent on this at Wal-Mart is money well spent.
Played counter strike for a while as well.
Quake one two and three.
Unreal Tournament was good and 2003 is good. I need to re-install but I lost my case with the code. I want to install that star wars mod on it to try.
Army Ops is a great game. I haven't played for a while now but it's free from any Army recruiter or free download off the net. Its a little big though and hardware requirements are a little steep. Great game though. I love the Pipeline map!