dotProject is a volunteer supported Project Management application

phpCollab is an open source internet-enabled system for use in projects that require collaboration over the internet.

PHProjekt is a modular application for the coordination of group activities and to share informations and document via the web

Online project management with team collaboration, user management, etc

ProjectPier is a Free, Open-Source, self-hosted PHP application for managing tasks, projects and teams through an intuitive web interface

MantisBT is a free popular web-based bugtracking system

Sugar CRM is the worlds leading provider of commercial open source customer relationship management (CRM) software.