Very old indeed but I've been on Carrion Fields a lot lately, revisiting old haubts, and it's still as fun as I recall. Uniquely for a MUD they even released on Steam with a client package and everything.

In the past I took characters very seriously and any time I died (let alone faced down the inevitable permadeath), it was emotionally crippling. This time around I'm mature enough to see the silly and just have fun with it.