This blog has a great idea on how to make a watercolor or gouache pallet out of an altoids tin and old milk caps. It's seriously very cool. I was thinking and I think I've seen out there a blog with instructions on how to dome something similar with sculpy or fimo clay. The milk caps are the fastest I've seen thus far though. How easy is it to simply hot glue those in? I've also seen one where the guy used tin snips and created dividers with sheets of metal.