Kaiser's Tengelmann -- headquartered in Mulheim, Germany, with more than 500 stores throughout the country -- recently installed a digital signage system in 13 of its stores. On average, each store has 10 digital screens: Two large freestanding units near the entrance and eight departmental screens in areas including produce, wine, meat and bakery. The content varies by department, with a mixture of information about that product category, special offers and general Kaiser's advertising.