Step 1: Materials & Tools
24" Horizontal Organizer
4 x 1.5" Zinc corner braces
8 foot indoor extension cord
2 x 13W CFL bulbs (I would have preferred a round CFL with Edison adapter but I couldn't find one locally)
"Round metal electrical box cover" with two bulb sockets
8 oz. (sample size) Valspar Pantone Green Flash paint
Disclaimer: Please be careful when using power (or any) tools! I am not responsible for your safety, so be smart out there!
Step 2: Size & Cut Pieces
Step 3: Paint
Step 4: Assembly
After painting, the cut shelves were attached with screws after drilling pilot holes to prevent cracking. I didn't take into account the top pieces were a little smaller than the pieces I had cut from the shelves and ended up having to use some corner braces to mount the one to the top of the box. A little bit more preparation on my part would have prevented a lot of pain and improvisation in this step.
The light fixture was mounted against the hole drilled in the top, and the wires were connected to the extension cord using wire nuts (not pictured). As the bracket screws were sticking out the top, I decided to add the other end piece from the shelving unit as a second layer to the top to clean up the overall appearance and make it less likely to bite the user.
This particular light fixture is tricky to adjust, so I'd suggest something a little different if you want to build your own. The two 13W CFls seem to put out plenty of light and the 6500K color temperature seems to give a good color for the background. As this was a gift I didn't get a chance to take any pictures with minifigs in the box, but I think it will work out well.