Paranoid TelnetD is written in straight C with few dependencies. It is intended for use with embedded or legacy devices (like the hand-scanners used in warehouses) that communicate via telnet. It features: 'telnet only' user accounts, separate from the system authentication (so only the specified usernames/passwords can login via telnet, and only via telnet); user, IP address, and MAC address whitelisting/blacklisting; chrooting with 'bind mounts' to allow access to certain directories under the chroot jail; and 'honeypot mode' in which all authentication fails and all events are logged at syslog 'crit' level.
WAWAS is a full PHP application server. The main server core listens to any IP/port and passes data to any mounted protocol on the listener. Implemented protocols are HTTP1.1/1.0, Comet, Telnet, DNS, mail, and FTP. Each protocol runs modules that build response data based on the requests. Memory object persistence allows data and caches to be shared across protocols or time. All configuration uses XML. It can be launched as a daemon, with or without forked workers, and is nearly as fast as Apache in preliminary tests.
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.
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.
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.
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.