There is a plethora of Mindmapping software tools out there but PersonalBrain, using the metaphor of the working brain connecting neurons (in this context - parent thoughts) to a series of child thoughts (thoughts associated with the parent thought) offers a very simple moving functionality that allows the user to move from parent thought to parent thought in the process making connections a static mindmap isn't able to do.
The Creative Leadership Forum is now using PersonalBrain for business planning and has found it very useful for gathering the complexity of all the thinking that is taking place, strategic and tactical in this process, thereby offering a holistic view of its operation from a broad and close-up visual perspective.. There is a free version and it is very easy to start straight off. Like all software there is some practice required to get up to speed with its entire functionality and there is a very good instructional video that can be found here.