It's a nonviolent MUD. (Multi-User Dungeon)
You can either launch via SLIME by evaling mire.el from within Emacs (preferred since it gives you access to the REPL) or by the included mire.sh shell script.
Dependencies (clojure, clojure-contrib) are included, though you will need a JVM on your system.
To connect, simply telnet to port 3333, or hit M-x mire from within Emacs if you have used mire.el.
Copyright (c) 2009 Phil Hagelberg Licensed under the same terms as Clojure.