tn5250 is a 5250 terminal emulator, used for connecting to IBM's AS/400 (now known as eServer iSeries) midrange computers. tn5250 implements TN5250E, which means it is capable of device name selection, and printer sessions. The emulator supports color, 132 column mode, and most other features found in 5250 terminals and Client Access' 5250 emulator. While tn5250 is text-based application, a script is included to run it in an xterm properly. If you don't know what an AS/400 is, this program will probably not be of much use to you.
MudMagic Mud Client is a GTK/GNOME multi-platform MUD client. It provides aliases, triggers, multiple connections, plugins, MCCP, ZMP, MSP, tabbed sessions, ANSI color, and a game list that can be updated from mudmagic.com. It is configurable on a per-session basis. Plugins include an automapper, database, and note pad.
KildClient is a MUD client written with the GTK+ windowing toolkit. It supports many common features of other clients, such as triggers, gags, aliases, macros, timers, and much more. But its main feature is the built-in Perl interpreter. At any moment, the user can execute Perl statements and functions to do things much more powerful than simply sending text the the MUD. Perl statements can also be run, for example, as the action of a trigger, allowing you to do complex things.
The Poor Woman's Telnet Server was quickly hacked together to provide a simple cross-platform telnet server. For non-Windows or non-Unix operating systems, you must adapt the call for the system shell. It is not advisable to run such an program on a production server, but for software development and testing purposes this program can satisfy some needs. It doesn't require a password and starts a system shell as the user who started the server.