The PLExD Toolkit | Promethean Learning Experience Design
A collection of free and open source tools for project management, graphic design, collaboration, audio, video, and other utilities.
Five free Microsoft Project alternatives - TechRepublic
Free options for managing projects. Some are open source. I've had mixed results with GanttProject in the past, but I may try some of these others.
Projity
OpenProj is an open source project management desktop application