Our school (NBCS) is going through a major reform of not only teaching styles and pedagogy but learning space, both physical and virtual. If you would like to see some of the blog posts by my principal about this visit http://imaginelearning.tumblr.com/.
This site allows students to create mind maps online. These can also be downloaded as PDFs once created. There is also an iphone app that they can use. A bonus is that more than one student can work on a mind map at the same time