Lightboxes are great - I set up a quick one as an expriment a couple of weeks back.

I used one of those plastic storage boxes - they are about the size of a cardboard box, but made of "smokey" plastic - nice to diffuse the light, with glossy white paper sheet as base/background - worked brilliantly. I only did a quick test with one camera flash, but the results were great, so when "proper" light is set up it will be even better.