It all depends on what you do and what you are willing to do. I've starting cutting scraps that are less than a fat eighth into squares. I have one drawer with 2 1/2 squares and one with 3 1/2 squares. I figure with then get fullish I'll start making scrappy quilts out of them. I also have a drawer for all my extra or orphan quilt blocks with a similar plan. My last step before I consider a quilt finished is cutting the left over scraps and binding length into squares for my drawers. I feel much better about my stash since I started doing this. Now I don't have random odd pieces all over the places. My totes are for yardage, fatquarters and jelly rolls. Everything else gets cut down to squares. Everything left from the trim down goes into a box and when it is full I give it away or find a home for it.
Bonnie Hunter has a great method, that's actually where I started but I only do what I know works for me.