I keep small pieces in ziplock sandwich bags. I have the plastic bins and sort by color. When I am looking for a piece the bags slide and are much easier to sort than digging through fabric pieces. I reuse the bags when I finish off a piece.
If you want to put every last scrap to use, take it to Goodwill or such. Mark the bags "Recycle" They can sell the unwanted fabric and clothing which is then recycled and kept out of landfills