Fantasy
Dragonlance, Dungeons & Dragons, Materia Magica, Medieval, Tolkien, Wheel of Time, A Tribute to Katlyn, Aabsolom, Abysmal Realms, Ages of Darkness, AlexMUD, Aurealan Realms, Auric, Avalon, The First Age, Avatars of Cassiopea, Avendar
Horror
Brek'Tyr Battleground, Haven of the Embraced, Lurking Fear II - Vampire Role Play Guide, Primal MUD, The Old Vampire Wars, Vampire Wars:Bloodletting
Resources
Encouraging Roleplay Over Rollplay, EverQuest Wedding Scripts, Roleplay Central, RPG Links, Talzhemir's Ideas on Online Roleplaying
Science Fiction
Star Wars, Aliens vs Predator, Decay, Eyecon2100, Gundam Wing: Endless Waltz Mud, Iconoclast, Necrotelicomnicon
Lythlandria's Batmud Castle
Guide to playing Batmud. Features maps and FAQs.
Myriad Magic
Guidelines, fiction, spells, game manual, races, professions, features, maps and tools.
Netherland
Features race and class information, rules, and clan information.
Nodeka
Game overview, connection details, game guides, message boards and contact details.
Shades
Based on a land of mystery and magic includes help files and player information. Site includes a Java client for direct web connection to the game.
Shades of the Past
A MUD set in the world of Kyderria. History and maps of the world are located on the site. Roleplaying encouraged and limited pkill. SotP offers 8 races, 6 classes with the ability to reclass to a dragon or shade, clans/guilds, quests and tournaments with prizes.
Terris - Ranger Guild Scribe's Office
Information can be found here for both those interested in the MUD game called Terris and those specifically seeking ranger guild information.
The Sentaari handbook
An Achaea support site. Provides detailed information on the Sentaari.
TriadCity
A free large-scale multi-user role playing game with a literary orientation, currently in beta.