Description:Digital advertising agency Avenue A-Razorfish wants to bring brand experiences to the "fourth screen" - a screen beyond the silver screen, TV, and computer. The term "fourth screen" is sometimes used to refer to mobile phones, but Avenue A-Razorfish has envisioned something larger: the storefront window. Consumers will be able to interact with a brand's website through storefront touch-screens, according to Emerging Media VP Terri Walter.(2:49)