Project management software is not just for managing software based project. It can be used for variety of other tasks too. The web-based software must provide tools for planning, organizing and managing resources to achieve project goals and objectives. A web-based project management software can be accessed through an intranet or WAN / LAN using a web browser. You don’t have to install any other software on the system. The software can be easy of use with access control features (multi-user). I use project management software for all of our projects (for e.g. building a new cluster farm) for issue / bug-tracking, calender, gantt charts, email notification and much more.
Obviously I’m not the only user, the following open source software is used by some of the biggest research organizations and companies world wild. For e.g. NASA’s Jet Propulsion Laboratory uses track software or open source project such as lighttpd / phpbb use redmine software to keep track of their projects.