I had this flash of inspiration in the middle of the night last night. In Writing Workshop, my students are on the brink of making "boxes and bullets" to outline a thesis with subordinate ideas for their personal essays. And then, following the Units of Writing model for essays, we're going to organize things physically by having three little "subordinate" folders, inside their big drafting folders. I know, this totally seems dorky, to have put so much thought into this, but those three subordinate folders (which are just gonna be 8 1/2 by 11 inch pieces of construction paper, folded in half) will be filled with sticky notes full of ideas, quotes, examples, and mini-stories which fit with the corresponding subordinate idea. Using sticky notes was the midnight flash of inspiration, because I realized how well they ought to stay in their designated folders (cuz they stick). And I also realized that when it's time to write drafts they can be arranged and rearranged, and moved from folder to folder, as my young writers experiment with different ways to order and organize their ideas. And they also come in lots of different shapes, sizes, and colors.
I remember when I used to set my night-time brain waves to work on complicated physics problems. I loved waking up with an answer to a problem I'd drifted to sleep puzzling over. So, this still happens, but these days the problems I puzzle out are far more complex and interesting.