ZOC is a popular terminal emulator and telnet client that supports telnet, modem, SSH 1 and 2, ISDN, serial, TAPI, Rlogin and other means of communication. Its terminal emulator supports Xterm emulation with full colors, meta-keys, mouse support, and local printing; VT102, VT220, and several types of ANSI; and Wyse, TVI, TN3270, and Sun's CDE. Unique features include full keyboard remapping, REXX scripting, and support for connecting to named pipes.
PAC provides a GUI to configure SSH and Telnet connections, including usernames, passwords, EXPECT regular expressions, and macros. It is similar in function to SecureCRT or Putty. It is intended for people who connect to many servers through SSH. It can automate logins and command executions.
LDMud is an LP-class MUD engine, meaning it is object-oriented, with all object clases stored in unique files. The engine runs compiled bytecode to manipulate those objects, and the underlying simulated processor is a stack machine. It is a 3rd-generation LP-class MUD, being derived from Amylaar, which in turn was derived from the original LPMud. The game has no limitations on the nature of the game space other than the limits of your coding.
SecureCRT provides terminal emulation with secure remote access, file transfer (SFTP and X/Y/Zmodem), and data tunneling. Supported access protocols are SSH 1 and 2, telnet, telnet/SSL, and serial. It has emulation support for VT100/102/220, ANSI, SCO ANSI, Wyse 50/60, Xterm, and Linux consoles. It provides session management and tabbed sessions in one or more windows. The program is fully scriptable via VBScript, JScript, PerlScript, or Python.
Soiled is a Flash-based telnet client and terminal emulator, supporting both char-by-char and line-by-line mode. In line-by-line mode, it has some features that make it suitable for MUDs, such as aliases, macros, and hotkeys. Since it is implemented in Flash, it can be used from a Web browser.
vmodemd is a telnet server designed to run old DOS BBS systems and door games. It listens for incoming TCP connections on a defined port, does a minimal telnet handshake if needed, and then starts to proxy all data to a PTY which is bound to a dosemu virtual serial port. vmodemd supports any number of virtual modems, can display customized banners if all modems are busy, can terminate a serial app when a telnet connection is unexpectedly dropped, and run custom scripts before passing control to dosemu, allowing you to pass relevant data like incoming IP address to the DOS app.
libtelnet is a small library for writing telnet protocol handlers in C. It uses a fully correct state machine model and full RFC 1143 (Q Method) option negotiation. It includes optional support for MUD-specific protocol extensions such as MCCP2 and ZMP. Several test programs are included, such as the very useful telnet-proxy utility.