One column for each thread, spaced out so parallel developments are, well, parallel. (The image only captures the part that could fit on my screen; it goes on for about half a screen further below.) I was pleased with how easy it was to pace things out this way, and see which things needed to go together, and it allowed me to see where two vaguely defined events could become the same single event. And also which few events were the big-big-impact events that I'd want to build towards.
The only problem is I can't print it (too wide). So I'll have to do the actual scene-by-scene outlining sitting in front of the computer. But I think I'll survive.
Off to do my exercise, and eat something lunch-like, and then back to the outlining! With a little luck, I'll be re-starting the first draft tomorrow morning (or even tonight, if I'm really ambitious :D ).