I used to. Went through a variety of systems through the years, but the two longest stints were with Dungeons&Dragons and MERP, respectively. I was actually a game master for a MERP group, which, believe me, is a nightmare with all of the tables and combat rules. ("critical failure: you stumble over a dead, invisible turtle" WTF)
Now, not so much... There's only so much time in a single day. I still have a few friends who play.