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.
nms is a set of drop-in replacements for the CGI scripts found at Matt's Script Archive. They have been developed from the ground up to emulate their behavior, but in many cases are better written and more secure. The collection includes form mail, guest book, simple search, and counter scripts.
SimpleForum is a forum that is designed to work on all HTTP servers which support CGI. It is very easy to configure, and does not require the user to have knowledge of any programming language. It has all the basic functions that a forum should have and a lot more. Additionally, it allows you to change the appearance of the forum (font, font color/size, background color/image, etc.) to your liking. You can also set different languages.
WowBB is an innovative bulletin board with features including an auto install/upgrade, a WYSIWYG editor with integrated spell-checker, automatic time zone detection, smart caching, a visual CSS editor with real-time preview, users selectable by location, and search engine friendly URLs. It can read and write the database formats of Invision Board, phpBB, UBB.Threads, and vBulletin.