Design problem: The most convenient place to store sandpaper sheets of different grits is on individual shelves. But in a shop populated by air compressors/dust collectors/fans, it's easy for the sheets to get blown all over the place.
The solution: Ideally you'd have something to weight all of the sheets down, but individual paperweights would be a pain in the neck. So Izzy Swan came up with a clever way to have all of the different grit sheets weighted down by a single action/device, even if the stacks are of different heights. Here he shows you how he built it:
Swan has also released free plans for the design here.