If you like me then you probably have a ROS. When I finish using the disk for flatwork I never throw them away though - I toss them in my used sand paper bag because there is always a little more scratch to be had from them. I use the old ROS disks two ways;
1. I cut out the center and use it for power sanding
2. I fold the outer edge and use it for spindle sanding, etc.
Of course in the first case they work excellent but also in the second case they are great because the clothed side protects against overheating the digits.