Presenting complex information in a graphic way is a very powerfull means of communicating to many people.  Add to that the ability to demonstrate what-if scenarios and you can see why I fell in love with Xcelsius from Business Objects.

Mindmapping

One of the most powerfull ways to think about and articulate ideas is to create a mindmap

Over  the last few years, I have become a very big fan of MindManager a software tool that generates mindmaps and allows you to export them to many other applications.