I can't even remember the name of one of the ones I played anymore. I do know I was a coder for a little while on Legends of Excalibur (still have a few characters there as well as my immortal (but it is a retired immortal so no powers)).
The one I can't remember had something like "the 3rd" or "the 5th" in its name (I believe it had to do with the revision though). Last I played it there were your main standard D&D type classes, mage, warrior, thief, cleric, ranger. Pretty much the only class that could heal was cleric (ranger had a passive healing effect if I recall). You almost absolutely needed to group due to this. You could multi-class, however, if you did, you main class ability would take a penalty. The biggest thing was that equipment was limited in the game (i.e. there was only 10 instances of a certain weapon or armor allowed to be owned by players). Each time you logged off, you needed to log off in a safe and pay a tax on the equipment you logged off with. I believe there was also a tax on certain items each day (even if you were not logged in). If your account didn't have enough gold and couldn't pay the tax, the items were removed. Items would also get damaged and eventually destroyed in battle (you could repair some things, but some of the real limited ones could not be). You could also see how many of certain items were out there and there would be races on getting a group together that could handle the MOB that would spawn with the rare items. Most of the powerful MOBs could easily wipe many teams, and not only that but they would track you down if you ran away (even back to the main city, killing everyone/thing that came in their path), some could even summon you back to them.
It was always interesting since there were only a few rooms that were truly safe (no-summon, no-mob), and you would see lots of people holed up in them whenever someone screwed up and awoke one of the mega MOBs and managed to get away (usually a thief who thought his sneak skill+bonus was good enough to get past it). And everyone would see when someone got killed. There was also a pretty steep penalty for being killed (major loss of exp), even going negative. I don't remember if you physically lost levels, but I do remember you lost some stats. You could also convert your trains/practices+exp into certain bonuses (such as increased hp/mana/stats), which is essentially what the end game turned into.
EDIT: I found/remembered the name, "Renegade Outpost 5" (had an old alias in one of my linux systems which had it).