I find mind maps very useful. I like to categorize things by branch (and use the number, etc. icons to cross-reference sometimes.) It's not perfect, but it's

I find mind maps very useful. I like to categorize things by branch (and use the number, etc. icons to cross-reference sometimes.) It's not perfect, but it's better than reams of text. I think sometimes the primary value of the mindmap is the study I put in building it.