XMind is an open source project that contributes to building a cutting-edge brainstorming/mind-mapping facility, focused on both usability and extendability. It helps people in capturing ideas into visually self-organized charts and sharing them for collaboration and communication. Currently
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supporting mind maps, fishbone diagrams, tree diagrams, org-charts, logic charts, and even spreadsheets. Often used for knowledge management, meeting minutes, task management, and GTD. [Less]