1. A smart home system network comprising: a plurality of smart-home devices that are distributed among a plurality of homes within a geographic region, each of the plurality of smart-home devices having a primary sensor that senses conditions central to the core operation of the respective smart-home device and a secondary sensor that senses conditions that are not central to the core operation of the respective smart-home device, the plurality of smart-home devices including a thermostat, a smoke detector, and a camera, wherein: the primary sensor of the thermostat is related to the primary function of controlling a temperature and the secondary sensor of the thermostat is one or more sensors selected from the group consisting of: a seismic sensor, an audio sensor, an acceleration sensor, and a radiation sensor; the primary sensor of the smoke detector is related to the primary function of detecting smoke and the secondary sensor of the smoke detector is one or more sensors selected from the group consisting of: a seismic sensor, a temperature sensor, an audio sensor, and a humidity sensor; and the primary sensor of the camera is related to the primary function of video monitoring and the secondary sensor of the camera is one or more sensors selected from the group consisting of: a temperature sensor, a seismic sensor, an acceleration sensor, and a radiation sensor; and an event detection processor programmed and configured to detect an event from information gathered within the geographic region according to the steps of: receiving said sensor measurements being provided by the secondary sensors of the plurality of smart-home devices within the geographic region; analyzing selected ones of said sensor measurements to determine whether an event has occurred, wherein the event is a geographically distributed event selected from the group consisting of: an earthquake, a tornado, a power outage, and an extreme local weather event; and generating at least one alert identifying the detected event; wherein the determination that the event has occurred requires processing of at least two of the sensor measurements provided by the secondary sensors of the plurality of smart-home devices within the geographic region.