Behold: A Light... With a Diffusion Panel.
FYI, I am working on a pretty in-depth multimedia project for Strobist that will show many really cool things that can be done with these easy-to-make panels. They are a natural fit for speedlight users.
But you'll definitely want to check out what X-Pose has going on, too.
And while you are at it, a little thinking exercise:
How could he have done the whole thing - diffused light source and "cookied" trees - with just one flash?
Yak about it here.
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