Free mind mapping (and related types) software. There are regular inquiries on Twitter and in forums about free mind mapping software, so to provide answers, InformationTamers have put together this list.
We built this article, with permission, using the most complete source for details of information mapping software on the Web: Mind-mapping.org. Hat tip to Vic Gee who put Mind-mapping.org together and kept it up to date for years. [Update: I took over that site in August 2013.] Le Mercator de l'information. A visual exploration on mapping complex networks.