Keep track of how much water and energy you use when you take a shower
Get notifications when you send/receive mail in a physical mailbox.
A mousetrap that lets the pest control companies provide fast response and gather relevant data about vermin control
Networked Sound Meters, noise levels in apartments, alerting the noisiest offenders. Exposing the noisiest cities.
IoT Fire Alarm (features: smoke/CO2 sensors, occupancy sensor, image recognition, alerts)