Smart Sidewalks is driven by two competing aims: to pack as much function into a single device as possible and to reduce the phonebooth’s footprint. “Everything” –communication, sustainability, and wayfinding is squeezed into “nothing” – a 6” wide interactive strip that folds up from the sidewalk. The design works within the existing 5’ sidewalk grid and has two main components. The first lies flush with the ground, and introduces a combined sensor and display with storm runoff storage below. The second stands vertical and functions as a touch-screen, Wi-Fi hub, energy source, charging station, and a range of other functions. In short, a location tethered smart-phone. The bent form is shaped by accessibility, viewing angle, and optimal solar exposure. A curb-cut bleeds storm water into storage cells dissipating it into existing soil. Sidewalk space is freed, putting to work the invisible space below.