In bookshelves I like backing them with wallpaper or contact paper. It adds nice color and pattern to the space. Here are some nice contact paper options that you can use for any shelving. I am thinking in the next couple of months I might line the back of my food pantry to add some fun color!
beige damask/bright pink floral/cane beige/distressed damask/bright multi colored floral/blue greek spiral/pink damask/blue geo