I miss Everquest (1). I really do.
Actually this is quite ironic, because I am sure that I was addicted at one time - and I mean this in a bad way. I spent far too much time in a game that was a grindfest and basically punished you for playing it. My opinion of the game actually is still pretty bad.
Losing experience when dying, up to the point of losing weeks of experience, maybe levelling down and then having to get your corpse with all your stuff on it, yourself...