Formmail PHP Script
A tool to parse information submitted on any HTML form and send it to specified users.

Gallery Photo Album Management System:
A tool to create and maintain photo albums on your Web site.

Invision Bulletin Board:
A forum solution for your Web site.

PHP-Nuke Content Management System:
An advanced content management system.

PHPOpenChat Chat System:
A high performance chat engine.

PhpBB Bulletin Board:
A bulletin-board system built using the PHP language.

PostNuke:
A community, content, collaborative management system for building dynamic Web sites.

osCommerce Online Store:
An e-commerce solution.

Crafty Syntax Live Help:
Live Help Chat system.

PHP Support Tickets:
A simple, secure, and powerful solution to customer relations.

PHP Web Calendar:
Web Based Calendar system built using the PHP language.

PHPLinks:
An extremely efficient link farm with full search capabilities.

PHPLists:
Personalized mailing list manager/customer relationship management system.

PHProjekt:
An open source groupware suite.

XOOPS eXtended Object Oriented Portal System:
A dynamic object-oriented open source portal system written in PHP.

b2 Weblog:
A classy news/weblog tool (aka logware).