Often, buzzwords like cloud, big data and IoT delight our imagination with the promise of eye-blink solutions for large-scale problems, the marvels of worldwide cloud infrastructures or the peak performance of the most recent TOP500 clusters. In practice, most of the times we have to face small to middle-size problems that require more than a computer to be solved in a satisfactory time but do not require always the use of top HPC infrastructures. In this talk we will discuss some aspects of fog/edge computing that, associated with green IT efforts, may help reducing costs and improve the use of existing resources around us.