dd_chat (formerly known as dd_ntalk-door) is a chat system derived from ntalk to be used with the DayDream BBS. The dd_chat client is a "door" program for the DayDream BBS that provides an easy-to-use chat client for the dd_chat server. Unlike the original ntalk client / server system, dd_chat implements several features from DayDream's libdd as well as an extended command set. It integrates seamlessly into DayDream. It features private conversation, checking for remaining BBS online time, chat idle timeouts (five minutes, except when in "away" mode), support for an ANSI logo and ANSI help screens from DayDream's "display" directory, and updating user status in DayDream.
Volley is a modular client/server application for chat, file sharing, and so forth. It is similar to Hotline, except its modular design allows for the addition of more services than just the usual chat, files, and news; there could be multiplayer games, and online meeting tools such as virtual whiteboards.
Pipo-BBS allows you to install a BBS server and clients. You can chat via a nice interface with an unlimited number of people (as with IRC). This software is in a pre-release state; it is still very alpha, and can be difficult to even compile. It works under linux, MkLinux, SGI, HP-UX, and Solaris. The only interface for this BBS is telnet for the moment; an interface using GTK has been started. It has been translated into French, English, Spanish and German.
DBOX is a free communication package for ISPs. It supports a large number of message formats such as RFC/UUCP, ZConnect, Janus/Janus2, Alphabox, and GSbox. It is designed for large installations and includes a WWW package with an email/HTML gateway, an HTML online shop, support for POP3/IMAP4, and personal homepages with HTTP/FTP upload.
aGNeS is a solid BBS system from Vestris Inc. aGNeS allows threaded discussions, article searching, archiving, thread expanding and collapsing, etc. It allows to setup as many web boards as desired with totally different layout , using one CGI. The look and feel of your forum can be just whatever you like using template pages. aGNeS is web-administrable. There are tons of features and options.