One of the great enemies of every homeowner is moisture. Leaks are a persistent threat, and catastrophic leaks can wreak more financial havoc than a fire, because insurance doesn't always cover the damage. And though humidity and moisture sensors are relatively common, WallyHome is the smartest of its kind. You place the wireless sensors wherever you're worried about leaks, and they'll alert you to sudden spikes in humidity.
What sets these devices apart is an innovative communication protocol, that uses the copper wiring in your wall as a kind of WiFi boost, so they can run for a decade without a battery change, and transmit from places like the basement or attic, where your router might not otherwise reach. As a bonus, WallyHome detects ambient temperature, so it can also provide the Nest thermostat with a more precise sense of the temperature in various parts of the house (rather than the immediate area around the thermostat). [$300 for six sensors and wireless hub; wallyhome.com]