Mind mapping, an aid to brainstorming
Mind Mapping is a specialized form of brainstorming which aims to capture relationships between ideas. Often a set of ideas do not form themselves into a list, but into a nest of relationships. While capturing ideas in brainstorming, you write them on the mind map as boxes with the name of the idea inside the box, and draw lines to other boxes related to the idea.
Speaking for myself, I find this greatly helpful as I find it limiting to try and force a set of ideas into an orderly list right away. Later on I might make an orderly list, but the most helpful thing is to first map out the relationship between different ideas. It is from that map which I make orderly lists, and it is through making the map that I can find clues telling me how to organize the thing being written, what points to cover, and even more about the purpose of writing.
For more on Mind Mapping, see http://www.mind-map.com/