- The Cold Project
- A group of programmers involved in developing in ColdC. ColdC is an object-oriented database language designed for setting up persistent online servers, such as MUDs.
- 16K MUD Competition Results - Results of a competition to write the best possible MUD server in under 16 kilobytes.
- [rec.games.mud]: FAQ #4/4: Servers at a glance - Detailed information about mud server types.
- Bluemud - Based on Varium project. Features documentation, research and project details.
- CGMUD - Graphical MUD system ported from AmigaMUD. Has a graphical MUD client written in Java and an efficient server written in C. CGMUD is not derived from any other MUD and has no licensing restrictions.
- CoolMUD Server - CoolMUD is an object-oriented, disk-based MUD server originally written by the creator of MOO. It has support for distributed processing. This version features some bug fixes in the server and improved in-database code.
- DUMB MUD - The 'Diabolically Uncrashable MUD Builder' project aims to provide a server that is first and foremost stable and reliable. The DUMB language is a dialect of Lisp.
- EmberMUD - Flexible open-source MUD engine, capable of supporting almost any role-playing setting.
- FTP.GAME.ORG Mud Archive - A directory of MUD server sources and other related files available for FTP, organized by server type.
- Kanga.nu MUD Server FTP Archive - Repository of MUD servers containing many old servers of historical interest, as well as new ones.
- KoalaMUD - Koala is a highly-distributed IP6/IP4 MUD server. It allows for very large game worlds to be distributed between multiple machines in a manner transparent to players.
- Majik 3D - A project to create a 3D online role-playing environment set in a medieval fantasy world. The server uses proprietary technologies provided by Taika Technologies.
- Momoko - An open source, modular, extensible platform for building multi-user environment. Momoko transparantly distributes objects over multiple servers and supports several scripting languages. Written in Java.
- Mud Development Mailing List - Focused on design and implementation of all MUD servers and systems.
- Muq - Ambitious distributed MUD server with a long list of features. One of the main aims of the project is to construct non-proprietary online communities based on free software.
- New MUD Code-bases - Catalog of new and original MUD servers for different platforms and programming languages. Includes short descriptions and links to the project web pages and their authors.
- The AIME Project - An open-source MUD engine, designed to provide as much flexibility as possible to the designer creating the online world.
- The Grendel Project - A MUD server for Win32 written in Delphi 5. Features include multi-threaded design, copy-over procedure and IPv6 support.
- The MUD32 Project - Notes on a Windows based Mud server.
- Tinymush 3 - Descendant of TinyMUD, supports multi-user communications in a text-based virtual world format.
- Valhalla Mud Engine - MUD engine by the original writers of the DIKU MUD server. Unlike DIKU, VME is available under a business license that allows commercial exploitation.