The large body of research on localization has been driven by the goal of providing users with location-based services, be it mapping and navigation or local alerts and advertisements. However, as we discuss in this paper, location information can over time provide deep insight about about a user, going well beyond the location domain itself. We argue that unlocking the wealth of information available from location is valuable and represents a new and promising frontier for location-related research, especially in the indoor domain. We call this Physical Analytics, analogous to Online Analytics, with footsteps taking the place of a clickstream. We describe research opportunities, challenges, and our initial investigation in Physical Analytics.