PBLang
- Bulletin Board System (BBS) written in PHP. Customisable and with many professional features, it does not require a database.
- http://sourceforge.net/projects/pblang/

eForum
- Web discussion forum. (Java)
- http://www.jcorporate.com/html/products/eforum/eforum_descrip.html

VAXbb Project
- A fast, text-based bulletin board system for the Web. (Perl) [GNU/Linux, Unix]
- http://www.omar.org/opensource/vaxbb/

Phorum
- Web based discussion software. (PHP)
- http://phorum.org/