I played Runescape within a few months of it coming out. I still do play, but on a different account then the one I started on. (I remember my old account was only 3 letters long, lol)
I've played Adventure Quest too. It was good until they made a members part, and if you were free-to-play, you had to wait for an hour just to get in a server. At least I think that was Adventure Quest.....