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.
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.
WCN:Talk (originally called "FutureForum") is a Web discussion forum written in Perl and MySQL. It has many options, including message selection and sorting on the top index page. It also has collapsible branches, a menu that toggles between 'no menu', 'simple', and 'advanced' modes, full text search capability, the ability to send email to the admin and original poster, and many other features. It includes password protection, HTML templates, file uploads, message subscription, multiple discussion sections, and a lot more.
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).