Sewmom,
I was considering the cubes but most of my stuff is not 16 inches deep. Folding fabric around comic boards is only 8-9 inches deep and if you want to store fabric on a bolt, you couldn't store it in the cubes. My shelves are only 10 inches deep so I put my scrapbooking stuff (mostly 12 inches deep) on the bottom shelves. The white boxes on my shelves are also Ikea and they are 11 inches wide, 14 inches deep and 7 inches tall so two would fit per cube but mine are turned sideways and work fine. The 10 inch deep billy shelves are $79 and the 16in deep shelves are $99. you can also buy doors for the shelves if you want to hide some mess.