I have seen (and coveted) those ink cube holders on YouTube that all my favorite paper-crafters use, but, cheapo that I am, I figured I could probably make one myself from foam core board.
Here's how I did it:
I cut closely around the base of the ink cubes with a very sharp X-Acto knife, rounding the corners like they are on the cubes, and cutting completely through to my cutting mat. I glued the piece with the cutouts to a solid piece of foam core, and am thinking of gluing a piece of that rubbery, webbed sheet that keeps things from slipping (what do they call that, anyway?), so it won't move around on my desktop.
The cubes and their lids fit in it so snugly, I can turn it upside down without them falling out! It holds 4 cubes and their prospective lids, or I can use both the front and back rows for just the ink cubes, if I'm doing a lot of colors.
I'm pretty much in love.