This is what I get when I have no PaD photo and it is pushing 8:30 PM. . .
In a last minute rush to come up with something, I grabbed my trusty model (my son), an actual umbrella (not a photography umbrella), my strobe, ebay triggers, and some elastic bands. I was able to get the strobe (580EX2) to stay in place up inside the umbrella with a single elastic to secure the hot shoe end of it.
There was still some light left outside, but not enough ambient to actually affect the photo. With the light from the strobe pointing straight down, it looked like a pitch black night.
Of all the shots, this was my favorite, even though there is no way of telling that he is standing outside, on the grass, barefoot, holding an umbrella. I might have to work on this kind of shot, perhaps mix it with a drinking glass. . .