bbs100 is a BBS in the style of DOC and/or YAWC. DOC is a style that remotely resembles Citadel. What's special about bbs100, is that it's a single process daemon that handles all connections at once, while consuming very low cpu resources ( < 1%). It can handle over a thousand simultaneous users. It is highly customizable, is easy to setup, and has many configurable features. bbs100 is almost a must-have for people that want to run a DOC-style BBS.
Citadel is an advanced messaging and collaboration system for groupware and BBS applications. Users can connect to Citadel using any telnet, WWW, or client software. Among the features supported are public and private message bases (rooms), electronic mail, real-time chat, paging, shared calendaring, address books, mailing lists, and more. Unlike other collaboration servers, Citadel provides its own data stores and is therefore extremely easy to install; you don't have to "bring your own" email and database because they're built in. The server is multithreaded and scalable. In addition, SMTP, IMAP, and POP3 servers are built-in for easy connection to Internet mail. Citadel is both robust and mature; it has been in production since 1987.
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.
LysKOM is an online, text based, interactive discussion system sort of like a mix between Mail, News, IRC and a BBS system. It's modeled after the KOM system that was available to DECsystems running the TOPS-20 operating system ages ago. The web site for LysKOM is written in Swedish, but the README files on the FTP site are in English. Both the server and (some of) the client(s) can speak both Swedish, English and other languages. LysKOM is a client-server system. This project is the server software itself.
mconv is an Internet BBS modelled after Monochrome BBS (menus rather than a command line). It includes several utilities for the conversion of BBS attributes to plain text, ANSI colour text, and HTML. It can also convert session logs and scrollback buffers to BBS format so they can be viewed in the BBS or in the included standalone file viewer.
Ncohafmuta is a text-based chat server that is designed for access from a telnet client. Its purpose is to allow users to communicate in a configurable environment in realtime. It allows users to create accounts with their own settings and optional personal information. Rooms are the basis for communication, whether private or public. Other features include internal email, email forwarding, a configure script for multiple Unices, support for cygwin under Win32, macros, games, a ranking system with access to more commands, ANSI coloring, banning, async DNS, soft/hot-rebooting, detailed, organized logging, and an internal Web server port.
VuohiMatik is a BBS software designed with large BBS systems in mind. It has filearea operations which work well on tens of thousands of files online, giving the end-user a uniform interface to perform quick selections and searches on the fileareas using various search conditions. Otherwise, it provides similar capabilities to AmiExpress and DayDream.
WebCit is a Web-based, AJAX-enabled frontend to the Citadel groupware/collaboration system. It is an attractive Web middleware layer that allows user-friendly access. By combining WebCit and Citadel, you can have a versatile online environment with many users concurrently accessing the same system using the user interface of their choice (text, Web, or downloaded client software).