I have 5 cabinets in my sewing room (15" deep BILLY bookshelves from Ikea, with doors). I bought extra glass shelves for them, and so in one cabinet, about half of it is glass shelves. I have some square trays (also from IKEA); two of them fit neatly on each shelf. I use the trays to stack my WIP onto, and then those sit on the glass shelves. The glass helps me be able to see what's going on; and when I want to work on something I just pull that tray out and it's all right there. For smaller projects I can even stack the trays 2 or 3 high on my shelves. (Larger projects mound up too high for that.) If it's a really large quilt with a lot of little pieces sometimes I have to use 2 trays for awhile...just depends on what's going on.