Xmind is an Open Source Eclipse based mind mapping tool. It can run as a stand alone application or as a plugin within Eclipse. The application looks good and has a decent set of features. It also lets you upload and share mindmaps on their site.
XMind, combined with online sharing service, provides a revolutionary way to enable both team brainstorming and personal mind mapping. With this major upgrade, we bring Web 2.0 concepts on community sharing into a popular desktop application. New Gantt view allows project managers to easily track project tasks and schedules. You’ll find many more useful and time-saving functions in XMind product family.