I use mindmaps every day for project planning, brainstorming, creating outlines, and implementing GTD. I find it to be significantly more effective than linear outlining and notetaking. To me, part of the appeal of mindmapping is being able to quickly and easily get everything out of your head, then organize it (Collect, then Process in GTD-speak), so software is the best way to go. Otherwise, I'd burn a lot of erasers...
I tried using Freemind for a while, but the interface turned me off - it's pretty ugly and inflexible. I use
MindManager by
MindJet, a
very well designed commercial mindmapping app, on my Mac. All the bells and whistles, with a beautiful interface and attractive output.
MindManager is a bit pricey vs. Freemind (it's hard to beat free), but IMO it's worth every penny. I use this app every single day, for pretty much everything. It's very helpful to use the software to facilitate the process, then be able to print out the map on a single page for reference when I'm away from the computer.
You can
download a free 30 day trial via the Mindjet website, which I found really helpful. If you decide to purchase a copy, make sure you buy from Amazon - you'll have to wait for a boxed version, but you can save $60 or so vs. buying direct from Mindjet. MindManager is available for both
Windows and
Mac.
Hope this helps! :-)