I've done the door knob too. I love it, but it makes putting it on a shelf hard :) When I do my books I always add a new endsheet (the piece of paper on the inside that holds the cover to the pages. Because I put a new one down, I can put ribbon all the way to the spine and then glue the paper down. It secures it nicely. You can use anything from hemp to ribbons. I have also drilled a hole in the cover on both front and back. You can string something through the back, and attach a stringed "loop" in the front. Then when you close it, you pull it through the loop and tie. The craft store also had what they called a "Book Bra" that I loved. It had a label on it that said "book bra" but it was a 2 inch stretch elastic with bra hooks on it.....cracked me up.