I use zlploc bags in sizes from snack size to 2 1/2 gal. to keep cut pieces together. Then those bags go into plastic 12"x 12" Artbin cases to keep everything for one project together. I have 2 stacks of the cases---working on 3. lol. This past weekend I found 14" x 14" plastic project cases (I think they are intended for scrapbooking, but they are perfect for quilting.) at Costco---a stack of 5 of them in 5 different colors---for $18 and change. That price is much better than the Artbin at JoAnn's even with the 50% off coupon. They don't have a carrying handle, but they have the same clasps as the Artbin so they stay closed securely.