The swarming behavior of ants, bees, termites, and other social insects has implications far beyond the hive. Swarm intelligence — the collective behavior of independent agents, each responding to local stimuli without supervision — can be used to understand and model phenomena as diverse as blood clotting, highway traffic patterns, gene expression, and immune responses, to name just a few. Swarm technology is proving useful in a wide range of applications including robotics and nanotechnology, molecular biology and medicine, traffic and crowd control, military tactics, and even interactive art.