I recycle Tide detergent boxes to make portable file boxes or portfolio cases. First, I start out with an empty 16.43 lbs. Tide detergent box (120 wash load size). This size is exactly the right size to house hanging file folders and other portfolio covers sized for 8 1/2 x 11 inch paper. Next, I cover the box with contact paper and personalize the case with my own decorations. This case is handy for carrying curriculum guides and other necessities. My students enjoy making these cases to use at home too.