Digital Library Wallpaper lets visitors ‘borrow’ ebooks by scanning your walls

Excerpt from this article:

Digital Library Wallpaper is exactly what it sounds like: a flat representation of books bearing QR codes on their spines. Using an online tool, buyers can pick between a handful of different designs, then assign titles to each volume from a pre-selected list of free content and do some minor visual customization. If visitors pull out their phones and scan the QR code, they can download the book to their phone or tablet.