And use wide masking tape over each cube as you are done so that when you (or the cat or the kids) knock it the screws don't disappear into invisible cracks in the floor.
Actually I tend to have strips of tape attached to my desk, with the sticky-parts up. The ends are turned over and stuck to the desk.
I stick the screw heads to the tape. They stay pretty well, are easy to get-to, and it's easy to arrange them as you want. I usually put them in a compacted form of the layout they were on the board.
