Freeplane

Freeplane is a free and open source application for mind mapping, knowledge management, and project management. It helps you develop, organize, and communicate ideas and information, with tools for building and navigating mapped information at work, in school, and at home.

Maps support rich text formatting, custom styling, and node formulas, and a command search makes features quick to reach. Scripting drives slide-based presentations from a map, and add-ons extend what the app can do.

Freeplane is written in Java using OSGi and Java Swing, so it runs on any operating system with a current version of Java installed. It can be installed normally or run from removable storage like a USB drive, which makes it portable across machines.