Annular maps – marching to a different drummer
Mind maps in function though not appearance, you don’t see annular maps so often, but they do provide a focus and a breakdown of topics, level by level, and a moveable mental focus which mind maps don’t support so well.
This is a fresh view that you might well find useful for some tasks, and the software versions are multi-platform.
More at WikIT.
[Update Feb 21 2011 – VisualMapper (Wallace Tait) has a new piece on Crystal Mapping.]