Xmind - Xmind is a brainstorming and mind mapping application.

TiddlyMap - An interactive concept- and mind-mapping plugin for the personal note-taking software TiddlyWiki based on the Vis.js library. It's free and open-source!

Mindomo - Easy-to-create and share mind maps, concept maps, task maps and outlines. Mind mapping software for Web, Desktop, iOS and Android. Mind map with us for free!

Wisdomap - Wisdomap Medicine is a study aid that helps medical students create differential diagnoses and suitable management plans from a presenting complaint and structured revision notes.

Freeplane - Freeplane is a powerful and free software for building mind maps.

IOctopus - IOctopus is an online mind map service for a dive deep into the mind for the best ideas.