"Books come to me in cardboard boxes, paper bags, reusable totes, children’s organizational cubes, rattan baskets, and plastic bins. These are all a welcome sight; the books will tend to be recently purchased and in reasonable condition. What I dread are the decrepit cardboard boxes or trash bags. Books schlepped in a rippling thirty-gallon plastic bag are not books in reasonable condition; they are books which have become recyclables or a mold hazard. And yet occasionally there are treasures." More at Popula