GanttProject is a free and easy to use Gantt chart based project scheduling and management tool.
It comes with:

* Task hierarchy and dependencies, milestones, baselines
* Gantt chart with an option to generate PERT chart
* Resource load chart
* Task cost calculation
* Export to PDF, HTML, PNG and CSV
* MS Project import/export
* WebDAV based groupwork

Visit http://ganttproject.biz to learn more