MUDs

Distant Lands
Entertainment, Games, Online, MUDs, Custom Driver - Distant Lands. Free text based fantasy roleplaying game.
http://www.dl2.net/
Online RPG, Adventure Game, Avalon; The Legend Lives Online RPG
Adventure Game, Avalon - Online RPG games multiuser world. Premier online RPG adventure multiplayer world. Online RPG adventure (Roleplaying Games or RPGs) with Windows and java game clients for instant RPG games play. Avalon is an online multiplayer role playing world which caters for those who know: the book is always better than the movie.
https://www.avalon-rpg.com/
the Home of MUD1 - British Legends!
Entertainment, Games, Online, MUDs, Custom Driver - British Legends. A port of the Compuserve incarnation of the original Multi-User Dungeon, written by Richard Bartle and Roy Trubshaw.
http://www.british-legends.com/cms/
Banished Lands : The Official Page
Entertainment, Games, Online, MUDs, Custom Driver - Banished Lands. Sections on online help, players, areas, rules and policy, clans and brethren.
http://banished.dentinmud.org
LegendMUD Official Website
The Official Home Page of LegendMUD (telnet://mud.legendmud.org 9999) These pages serve as an introduction, reference and as a repository of community history for LegendMUD.
https://www.legendmud.org/
Features forums, online status indicators, and references.
Materia Magica is an award-winning free, feature-rich text-based multiplayer fantasy RPG where action, adventure, and immersive role play occur in real time, twenty-four hours a day with hundreds of players worldwide.
https://www.materiamagica.com/
ymusk - Yenz's Mush Klient
Entertainment, Games, Online, MUDs, Clients - Ymusk. Tk mush client written in perl.
https://ymusk.sourceforge.net/
Mmucl - Mark's MUd CLient
Entertainment, Games, Online, MUDs, Clients - Mmucl. Tcl/Tk client with a console version.
https://mmucl.sourceforge.net/
Xpertmud - Linux KDE and Windows MUD Client
A cross-platform (Linux+KDE/Win32) perl and python scriptable mud client. Featuring a nice and stable plugin API and an example plugin for the btech MUX.
https://xpertmud.sourceforge.net/
gosclient - home
Entertainment, Games, Online, MUDs, Clients - GosClient. Client with most standard features and plugins.
http://gosclient.altervista.org/