A mind map is a diagram used to represent words, ideas, tasks or other items linked to and arranged radially around a central key word or idea. It is used to generate, visualize, structure and classify ideas, and as an aid in study, organization, problem solving, and decision making (wikipedia’s definition).
I use mind mapping software for 2 main needs in software development management: when I gather requirements from the customer and for use cases descriptions. The software I use is Mindmanager, but recenly I found that there are some reasonable open-source alternatives in the market.
Most of my customers describe me their business needs or problems, and sometimes they even have a general vision of a solution. When it comes to the “bits and bytes” of their requirements, they start to “think” with me: modules, features and fields are added and cancelled in this process. New insights that we have lead to changes. In the past, I used pencil and paper for this process. Now I use mind mapping software to do it. It allows me copying, cutting and pasting. In addition, it gives me and the customer a good perspective on the system as a whole. We know at any given point what parts are still missing in the solution. I manage BPM processes, so I developed a “checklist” map template for BPM systems requirements gathering, that I fill-in with the customer.
The second usage of mind mapping tool is while defining use cases, in the functional design phase. Same here, I have developed a template map for a use case. After I fill it in, I publish it to the intranet, and let the customer comment on it.

I am looking for a mind mapping software for illustrating ideas and thoughts, and also to literally creating mapping of stuff.
What do you recommend? because there are so many…