The possibility to have millions of computational devices interconnected across urban environments opens up novel application areas. In such highly distributed scenarios, applications must gain awareness as a result of opportunistic encounters with co-located devices, a departure from traditional reasoning approaches. We envision situated awareness as an emergent property of such networks, where bio-inspired algorithms are employed to coordinate interactions between devices through managing the lifecycle, distribution, and content of data. A congestion-aware, crowd-steering example illustrates this approach.