Photek makes a reflective umbrella with a diffusion screen called the Softlighter. Sets up and is priced like an umbrella, but acts like a soft box. Comes in different sizes. A local professional used one at one of our local Strobist workshops. I really like the light.
Great article. But one thing. When my subject was a person, having the softbox 18 inches from her face didn't work out so well. Normally, I would have the softbox about four feet away and meter it at F /8. I had an Alien Bee B400 at 1/32 power with a 40 inch softbox. I tried it on my daughter at about 20 inches after reading your article. But the flash at that distance was very unpleasant for her.