Freeplane began as a fork of the Freemind project. While maintaining comparability with Freemind file format, it has far outpaced in features and development. As of 3/5/2022, the latest Freeplane update (1.9.3) is 3/5/2022 vs Freemind was last updated (1.0.1) 2/5/2016. Active, helpful community.
Xmind - Xmind is a brainstorming and mind mapping application.
Observable - Interactive code examples/posts
FreeMind - FreeMind is a premier free mind-mapping software written in Java.
nbviewer.org - Rackspace server host Jupyter Notebooks from your github repo
vym - VYM (View Your Mind) is a tool to generate and manipulate maps which show your thoughts.
Jupyter - Project Jupyter exists to develop open-source software, open-standards, and services for interactive computing across dozens of programming languages. Ready to get started? Try it in your browser Install the Notebook.