AIME is a C++ MUD engine with an OO design, designed to provide utmost flexibility for the designer to create complex worlds. It has a fully-functional builder port, online interpreted specials code, and a flexible levels/quest/profession track system to allow the game owners to set up any world they can imagine.
Battletech MUX is an Internet based, real-time rendition of the popular Battletech board game. Players take to the front lines in their very own mechs, tanks, and similar implements of destruction. Featuring an internal scripting language called SoftCode, game admins may sculpt their sites into whatever they can imagine, be it small-scale combat or massive, galactic conflict.
CircleMUD is a multi-user dungeon game system (MUD). It is a derivative of DikuMUD Gamma 0.0. A MUD (Multiple User Dimension or Multiple User Dungeon) is a computer program which allows Internet users from around the world to connect to it, create fictional characters for themselves, and then interact with other real users as well as computer-generated entities in a virtual environment.
Crossfire is a multi-player graphical arcade and adventure game made for X. It has certain flavours from other games, especially Gauntlet and the rogue-like games (Nethack, Moria, Angband, and Ragnarok). Any number of players can move around in their own window, finding and using items and battling monsters. They can choose to cooperate or compete in the same world.
Deliantra is a client for Deliantra game servers. It offers an intuitive user interface for exploring the vast game world, a persistent minimap, powerful macros and keymaps, dialog-based NPC interaction, and easy configuration for the skill, spell, and item system. It is based on Perl, SDL, and OpenGL for high performance on modern systems, and works on both Unix and Windows. Ports to other platforms should be very easy and are underway.