What the?!?! Then again, you have to consider that this is the UK we are talking about, they have surveillance camera on every corner over there.
Flock's sensor, which it offers for $50 a year per house, logs the number plates of every car that drives into a street and takes a picture. The sensor could eventually provide facial recognition. Residents of monitored neighborhoods can opt-out of being tracked - but visitors, or people passing through, cannot.