Dust- and sun-protected fabric storage. I prefer to store my fabric stored upright - like it is in my LQS. I use foam core cut to the size of the space between my shelves - others use thinner, but stiff acid-free material to wrap their fabric on. You can see all your fabric at once, and it's much easier to take it out AND to put it back. In CT, I have mine on shelves with shades that roll down from the ceiling to protect from the sun. In AZ, my stash is in a closet.