I modified the factory cart coffee table plans to make a coffee table with a removable top for storage. The result was more Pottery Barn than Restoration Hardware. I put a piece of plywood on the bottom, to make an enclosed box. Then modified the frame under the 1x6's of the top, to make it fit snugly in the opening of the top of the box. The sides of the box were 1x12's I had leftover from another project. Actually, everything was leftovers, except the 1x6's for the top, and the castors. The 4 inch castors were painted flat black with high heat wood stove paint (also a leftover from refinishing our pellet stove). I used smaller castors, since the table was already taller than the original plans.
Satin Polyurathane (oil based)
Ralph Lauren Flour Sack White Latex paint