There are still a lot of MUDs out there, which I'd consider to be multi-player extensions of games like Zork. Some still draw 500+ paying accounts logged in at

There are still a lot of MUDs out there, which I'd consider to be multi-player extensions of games like Zork. Some still draw 500+ paying accounts logged in at peak times, and have characters that are 25+ years old, like Gemstone IV (play.net/gs4). I tend to explain it as "World of Warcraft without graphics", but "rapid-paced AD&D" is a fair approximation, too. The medium gives the people running the show a lot of flexibility in how they guide collaborative stories - no need to wait on art assets!