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.
ansistego provides terminal-level steganography for scripts and other ASCII files (ie, protection against 'cat'). It intersperses a text/script with commented ANSI codes that cause most terminals to clear sensitive lines as soon as they are written. Only a specified front text appears. The front text is embedded in the script using ANSI-cloaked comments, so that the text appears unaltered when the script is viewed with cat, but the script can be run without any decoding stage.
gtermix is a GTK+ telnet client intended for calling BBSes. It utilizes a custom VGA textmode emulating terminal widget that allows it to accurately render bulletin board systems as they were in DOS terminal programs. It currently features a GTK+ user interface, dialing directory, support for ANSI, vt100, Avatar, and TextFX terminal emulations, and proper rendering for DOS-style BBSes.