I’m not one who believes in destroying books, but I think the benefits outweigh the costs on this one.. There’s no denying this secret box awesome. All it takes is a big hard covered book about nothing that will never be picked up by anyone ever again.. and an exacto knife. Measure with a ruler the distance you want your box to be and try to be consistent as you tear each inside square out. If each cut is deep enough then this shouldn’t take too long. Be careful not to cut through the back cover though or else all the hard work will be for nothing. It’s also not necessary to cut every page out. If a smaller box is desired, then stop halfway. When the cutting is done, decorate it or leave it alone. Store it on a shelf with other books and keep secret stuff in it or leave it on your desk for a friend to check out and be taken by surprise when they go to flip through it!