AberMUD was my poison of choice, from 1990 to 1995 or so. I even went to the trouble of finding the source code and putting up an Aber Dyrt MUD on an ancient Linux laptop a few years ago, at tabidyrt.servegame.net port 8888 if someone wanted to walk down ancient text only paths to adventure 
Yyyup. Still MUDding occasionally, though the last one I played seriously was probably more than ten years ago. New Moon, I think it was called, not sure if it is still around and kicking.
I will boast that I was a founding member of a group that split off from a MUD that was called Wings when we left.
My friend is/was a major programmer who introduced me to Wings when we were in college. He was asked to split off and start a new MUD with a group of Wizards that had grown tired of the way things were administered on *Wings. *My friend recruited me to “defect” to the start-up game as well, saying the main group was really good at writing code but he knew in advance that they would need a foundation of social/literary/historical knowledge on which to base the new world.
I contributed some key ideas about the names and back-stories of places, the realm’s Origin story and pantheon, plus the way magic should work, how equipment should deteriorate, and how the economy should (and shouldn’t) work. One of the key differences in our MUD was that, while most of the other MUDs available at the time were really geared toward solo adventuring – yet often had groups of players’ characters attacking an opponent at the same time, we decided to make groups an integral and necessary part of the quests.
Since my actual programming skill wasn’t that great, I was handed some of the tedious-yet-creative tasks of designing and describing races and they way they move, the nomenclature and values of different cities’ currencies and exchange rates, and explaining how a feudal system integrated with a manorial system so the programmers could make it actually work. My most enjoyable projects were writing stories that the programmers would turn into quests, and in writing excruciatingly detailed descriptions for rooms and locations.
And then my friend asked, “How should we divide character classes and set up the experience and hit point tables?” and I knew before being asked that it was a prelude to “That sounds great! **You **do it!” and it would be excruciatingly tedious and mathematical. :mad: So told him, "Y’know…our karate instructor once said, ‘Learning this stuff won’t make you invincible; you’ll just learn how to get hit less – and how to not mind so much when you do get hit. And it won’t necessarily make you more powerful; you’ll just learn how and where to be more effective when your strikes land.’
That was clearly dodging the question 
but my friend thought about that for a moment and said, “Yeah! Build up skills rather than experience points and levels. No two characters will be alike!”
And that was the roots of a skill-based MUD. And we eventually broadened the model from combat skills to spell casting skills and then to crafting and other skills – all with the intention of making sure all the different combinations of skills would be integral requirements for solving quests. And the key in making awesome quests would be to require especially strong skills so that people would need to specialize in certain skill sets and then join together to apply those skills to different parts of the mission – again forcing (not just allowing) players to work in groups.
I created the name of the planet by combining parts of the character names of the founding programmers. The first name I suggested included my own creator name, but it was rejected because name of the initial founder who was hosting the game wasn’t first in the combination. The second name I suggested put the founder/host’s name first but I couldn’t figure out a way to include myself.
The MUD is still out there and it was apparently influential to the development of Ultima Online. IMHO it appears to have influenced the GuildWars skill point system, as well.
Throughout all that, I never was much of a player. I had been a player on Wings and got to a decently high level before I left. The fact that I gained most of those levels by solving puzzles (rather than completing quests) was one of the unsatisfying factors that led to my departure. I started as a creator on the new system and never really learned how the maze of streets and wilderness areas connected – first because there were no streets or buildings and later because I was able to just teleport anywhere I needed to be. I did create a character (you’ll never guess the name) and used it to meld into the crowd and listen to complaints and quest ideas.
And then a commercial BBS bought the game and that “resulted in significant staff turnover” which sort-of included me.
—Grestarian-sich-Karnak
The Wanderer
BTW, I hadn’t checked on this MUD in several months. Apparently my laptop had crashed or otherwise gone down. I just restarted it, so if anybody had actually tried to connect and failed, or would be interested in doing so, it’s up again.
So only then did you realize the hazard of creating a character with the name Bolt?
Oh my, yes. Played on two of the oldest ones that are still around. They’re both still up and running. I know this because I was IMMing on one of them as recently as last year. I still go back to that one every now and then and poke around - sometimes as staff and sometimes as a player. It’s always kind of bittersweet because it’s a dying hobby, but the damn thing has been up and running for more than twenty years and it’s still kicking. So long as there’s somebody around to keep the lights on and the code clean, it’ll keep on keepin’ on.