A year or so ago, I was in the library and by random chance (yeah, like there is such a thing) happened across Tony Buzan's book on mind mapping. I knew what it was, but had never actually used it.
I checked the book out and started experimenting with it. I was pleasantly surprised at how it enabled me to flesh out ideas I thought were already well explored.
If you're a visual thinker, mindmapping will score double bonus points with you.
Here are a couple links to get you started: