Unless you're on the wrong side of a Colombian drug lord, the kind of criminals who would break into your house are mostly opportunists. Use your car alarm to send them running. Photo by epredator.

The humble car alarm has been around almost as long as the car itself, first being developed by an unknown prisoner in Denver, circa 1913. To the security-conscious motorist, they make a lot of sense.

Discover 5 essential anti-theft devices: GPS trackers, steering wheel locks, immobilisers, alarms & wheel clamps to keep your car safe. You lock your car, double-check the handbrake, and walk away ...