COMPUTING RESEARCHERS AND practitioners are often seen as inventing the future. As such, we are implicitly also in the business of predicting the future. We plot trajectories for the future in the problems we select, the assumptions we make about technology and societal trends, and the ways we evaluate research. However, a great deal of computing research focuses on one particular type of future, one very much like the present, only more so. This vision of the future assumes that current trajectories of ever-increasing production and consumption will continue. This focus is perhaps not surprising, since computing machinery as we know it has existed for only 80 years, in a period of remarkable industrial and technological expansion. But humanity is rapidly approaching, or has already exceeded, a variety of planet-scale limits related to the global climate system, fossil fuels, raw materials, and biocapacity. (28,32,38) It is understandable that in computing we would not focus on limits. While planetary limits are obvious in areas such as extractive capacity in mining or fishing,