Those foam board light boxes do work nice. I usually make 1-2 a year and throw them out when I'm done for a while. They cost like $5-$10 to make and I don't feel like storing them. I store the compact florescents that I use, and the clamp light all come from my reptile cages and unused equipment.
If you use more clamp lights you can reduce those harsh shadows. I usually use 4 of them, clamped on to the sides and pointing at the corners. That gets a lot of light bouncing around in those boxes and gives nice, even, bright lighting.
I would post pics, but everything I did this year in boxes was on slides and color print film. My only digital is a little point and shoot Kodak. Hopefully this year I will get a digital body to go with my Canon set up.