Very intresting Joomla extension

Joom!FreeMind 2.1.1 is a Joomla! 1.5.x native component. This extension generates an appealing visual mindmap observing your menus,categories and sections. It makes use of FreeMind - a premier mind-mapping software written in Java and displays the published site structure by connecting the component to a menu, a menu item or to a simple hyperlink placed inside your articles. The name of the component is the same as the one we have chosen for the stand-alone tool (you might want to check this one as well, especially if you are using Joomla 1.0) but note that the previous versions (1.8.x) do not provide complete Joomla! integration. Version 2.0.4 made corrections to the wrong categories and sections links. Several display options and color variation schemes were added in the backend, and Joom!FreeMind 2.1.1 kept the two different ways of rendering maps by either using the sections-categories structure or the published menus. It also brings the option of rendering maps through an alternative flash based viewer if you do not want to use the java viewer on your site.

http://www.xinet.ro/en/current-projects/joomfreemind.html