Transforming IKEA furniture — and especially the BILLY bookshelf — has been done before. But when I saw this hack, I was truly impressed. Prepare to have a bunch of superlatives spewed your way, because it's really that good.
Ikea stool and white mongolian lamb cushion cover. Remove seat from stool, use it to draw two circles: 1 on wooden board, 1 on thick foam. Glue foam to board, lay flannel over board/foam staple to back of board. Remove back Mongolian