I do a lot with concept mapping. I use it in my work as an instructional designer and I use concept maps in writing fiction and technical work, and I am really interested in Compendium right now. What is Compendium? It is more than just concept mapping software. "Compendium is about sharing ideas, creating artifacts, making things together, and breaking down the boundaries between dialogue, artifact, knowledge, and data." Compendium is a free concept mapping software package by the Compendium Institute, a group formed by Knowledge Media Institute of the Open University of UK, Verizon, Center for Creative Leadership, and others to promote the compendium methodology.