PukiWiki ('PoohKeyWeKey' without any prolonged sounds) is a wiki implementation that works on PHP 4 and 5, outputs XHTML 1.1, has many plugins (including one for bug tracking) and skins (such as one for embedded browsers), enables English and/or UTF-8 configuration, and features case-insensitive WikiNames. The formatting rules are based on YukiWiki.
KDX is a powerful cross-platform BBS-style encrypted Internet communications system that provides messaging, news, file and folder transfer, voice chat (Internet Telephone), text chat, remote access, trackers, and more. It uses strong encryption to protect communications for security and privacy. It is useful for groups that need to collaborate on a project via the Internet. It is also very useful for remote administration of a computer. It uses a client/server architecture.
The Floranta AJAX libraries are used to build Rich Client Wikis. Editable sticky notes can be created and positioned over any Web page (even plain HTML), and are capable of behaving as if they stored their entire state in the page. Floranta enables collaborative teamwork and creative activities like cartooning and collage creation, personal notes, ToDo lists, and blogging.
BBSzilla is an extension for Mozilla-based browsers such as the Mozilla Application Suite and Firefox. It gives the browser the ability to connect to Bulletin Board Systems that utilize TCP/IP, such as Hotline servers. There is functionality for multi-user chat, single-user messaging, as well as server-side and P2P file sharing, threaded news, single-thread bulletins, and more.
Globe*Trotter is a guestmap. It allows Web site visitors to mark where they live on a map and include their personal comments, instead of merely tacking their personal regards onto the end of a long list. It benefits your visitors because they can easily read other's comments and add their remarks in a fun and novel way. It also benefits you, the webmaster, because more people will be likely to give you feedback and you will be able to see where your visitors are. A free hosted version of Globe*Trotter (with no ads) is available.