Visual Understanding Environment (VUE) is a MindMap tool with a lot more than that.
http://vue.tufts.edu/index.cfm from Tufts University (http://www.tufts.edu/)
The Visual Understanding Environment (VUE) is an Open Source project based at Tufts University. The VUE project is focused on creating flexible tools for managing and integrating digital resources in support of teaching, learning and research. VUE provides a flexible visual environment for structuring, presenting, and sharing digital information.
There is quite a lot to this and it takes some time to get the feel of it. For a start, as well as versions for Windows and Linux there is a version which can be integrated into FireFox using an extension called ZoTero (http://www.zotero.org/).
Some things which VUE can do.
It has been quite fiddly to get everything going. ZoTero has to be downloaded separately and installed in FireFox. The VUE addin for FireFox did not work intially, which was diagnosed as caused by the version of Java not being sufficiently up to date. The second time I installed it was much easier, and the Java was up to date.
I think my current view is that this is now my tool of choice for capturing information when browsing the web for technical papers. I won't any longer have to wonder just which file is which.
-- JohnFletcher