ProjectPier is a Free, Open-Source, self-hosted PHP application for managing tasks, projects and teams through an intuitive web interface. ProjectPier will help your organization communicate, collaborate and get things done Its function is similar to commercial groupware/project management products, but allows the freedom and scalability of self-hosting. Even better, it will always be free.
For the project management of Macminicolo, we use Basecamp from 37Signals. It’s a wonderful application that has done well for our company.
But, if you are a “do-it-yourselfer” the ProjectPier may be an option for you.