Project Useful is a free and open source project management system written in the Ruby programming language using the Rails framework. Project Useful is very new and under heavy development! The source code is available in the Project Useful GitHub Repository.
Project Useful implements the Scrum Agile methodology for project management. The process goes something like this ...
You are building a Product. People request changes or new features to the Product through simple Stories that describe one request. That Story is then broken down into the individual Tasks that are required to complete the Story. The Story is worked on during a short duration time block called a Sprint. Sprints typically last one to two weeks.
So, for a specific example, Project Useful is being developed in the Scrum fashion. The parts are: