I typically don't go out of my way to endorse software products and tools, but in this case I think MindJet MindManager deserves special mention. As the name implies, MindJet's core competency is in helping people to manage brainstorming sessions, but goes way beyond that.

Most brainstorming sessions are done on white boards and represent a discrete point in time. Maybe a recorder jots down the ideas before all is washed away. But the momentum of the brainstorming keeps going, yet the white board no longer exists to reflect the evolved ideas.

Surely there must be a software solution to this... and there is.

MindJet preserves your mind maps and provides an easy to use interface for repeatedly evolving and refining your maps.

Tools like Visio and Project are great, but they tend to impose more linear thinking. MindJet "nodes" dynamically readjust their positions as new ideas are entered so that you're free to pursue thinking in any direction without the overhead of reformatting or rearranging existing work.

And when you're ready to publish your MindMap there are export utilities to all Office applications. There's even a free MindJet Map reader that is similar to Adobe's business model where you pay to publish, but it's free to view.

I really love the ability to insert little task complete checkboxes that increment 25% every time you click on them (except towards the end where they realistically increment about 10%-15%).

I also find the priority icons extremely useful for figuring out how to "do first things first".