If your pencils, pens, Exacto knives and other cylindrical tools frequently roll off the edge of your work surface, read on. To keep such things from rolling away and falling off your desk, table, workbench or drawing board, simply place a nut up near its top. Nuts come in many sizes, so finding one that fits is easy. Just slip it on, and, if needed, add some glue; little cylindrical things will now stay put. And that's the On The House Tip for today.