Diva friend Vicki also tried some spray-painted backgrounds that got me kick-started to try it :) And she did more here.
I started out brayering 2-3 colors on each of my large papers and embellsihed by spray-painting with stencils. On the last big paper I had some white spots and experimented with an India Ink resist to see what the effect would be with the spray-paints. It was tough to do on a larger scale, but I liked the overall effect and drama of it.
Spray Painted Backgrounds