Last week I discussed the life-changing organizational virtues of the Musical Laundry Line. While the laundry line is great for keeping track of small items, at some point you might wish for a larger surface to work with. When you feel that no sheet of paper is large enough for your grand ideas, you turn to the wall.
A one-litter can of blackboard paint can transform a fairly large wall into a creative idea 
surface. Throw some coloured chalk into the mix and you can quickly turn into an idea-organizing master (or doctor, whatever your qualifications).
This is my attempt to organize one of the scenes in my chamber opera. After spending all day trying to do this on paper, I turned to the blackboard wall. Somehow seeing it all in large, simple blocks made it all seem much simpler.
The blackboard is also great for any kind of collaborative work. Break out the wine and the ideas start to flow on their own. And when the wall is not doing work duty, it can relieve you and your guests of any other artistic angst you might have accumulated along the way.
A small can of blackboard paint costs about $20 from a Benjamin Moore retailer. If painting your actual wall is not an option, you could probably try doing this to a large piece of plywood and simply lean it against your wall. I suggest a small railing on the bottom to catch the chalk dust, which fall surprisingly fast and thick. I also hear that you can paint white boards to use with markers.
Happy idea organizing!