Since I used to work at a quilt shop, I probably have the largest stash going. Actually, I have been going through it and reorganzing and donating what I won't use. Before, I would organize it according to color on 4 white bookcase shelves I bought at WalMart and put together. Now this does not include fat quarters---will explain those later.
Now that I am redoing my sewing room and am getting older and realizing that I would never be able to use up all this fabric, I have started grouping ones that I know I purchased for specific projects together in rubbermaid or sterlite plastic containers depending on size of project and labeling them. They all are fitting on 2 white wire covered shelves that I have added, at least for now. The others are being shelved by color on the white shelves. Any fabric I am letting go of is going to a group in my hometown called "My Very Own Blanket" as they make quilts for foster kids in Ohio and teach the women prisoners at the prison in Marysville how to make them which makes me feel good that they are doing something to help society. As for fat quarters, I bought 2 wire racks that hang on the doors that are for canned goods or spices in the kitchen supply areas. If you fold the fat quarters in half and half again they fit great and I can reach them at a moments notice.