Cao Gadgets is attempting to fill that niche with its functionally named Wireless Sensor Tags -- small devices which monitor movement and temperature, notifying you if anything's amiss.

ENGADGET: Wireless Sensor Tags alert you to movement and temperature changes, fit on your keyring

With binoculars you can monitor every movement on the Ethiopian side - including Dongolo hill, which I had visited with the Ethiopian army.

BBC: De-mining in the Horn

Telford and Wrekin council said it was drilling bore holes between the Jackfield tile museum and the Boat Inn to monitor the movement of the land.

BBC: Ironbridge Gorge stabilisation work starts