I quickly filled the shelves of my Billy with small paperbacks that used very little vertical space. I started scouring the as-is section for a spare shelf, in

I quickly filled the shelves of my Billy with small paperbacks that used very little vertical space. I started scouring the as-is section for a spare shelf, in hopes of fitting a few more books into the space. After a few searches with no luck, I hit google for a recommended Ikea hack, and was pleasantly surprised to learn they actually sell extra shelves: http://www.ikea.com/us/en/catalog/products/20265301/ http://www.ikea.com/us/en/catalog/products/20265301/