I have been looking at bookshelves for the kiddos bedrooms, I wanted to double them us as ornamental shelves too. I seem to keep coming back to crates. you can stack them in all ways, shapes and they come in a range of sizes. You can paint them, add wall paper to them, customise them however you like. Just four or five crates can make lot of shelving, depending on how you space them out ( see bottom picture). You can pick them from your local fruit and veg man, local markets or you can buy them online from cratesforyou.com.