Searching the Internet has become an almost reflexive act. Each day, tens of millions of global citizens fire up their personal computers and handheld devices to troll for information on products or to glean insights that will help guide business decisions. Yet the economic value of this enormous current of search activity remains largely unknown. Current estimates rely mainly on brute measures, such as the number of searches performed or advertising revenues reported by search companies themselves. These estimates fail to take account of how trillions of clicks combine to boost productivity, open new pathways to problem solving, or simply make life easier.