Burglar Botherer

Most home security devices work on the principle of the alerting of other people, and offer no further deterrent to would-be burglars.

At the other extreme, devices designed to cause permanent harm would be illegal in most countries (except for personal defense), and though tempting to those recently burgled, are probably not desirable.

Designed for homes that do not need opening windows (for example, high rise apartment studios), an air bellows in the ceiling headspace (or utility shaft) designed to displace about a cubic metre of air in less than a second could be installed. It would sit within a sealed link between the ceiling and the outside atmosphere, with the front door replaced with a rudimentary airlock design - say a revolving door (the seal wouldn't have to be perfect).

When the alarm is tripped, a verbal warning would sound, followed by the rapid modulation of the air pressure inside the apartment. This would play havoc with the burglar's internal airspaces (particularly the eardrum), causing him/her considerable discomfort.

The glass in the windows would need particularly strong mountings to prevent them being blown outward (or smashed by an enraged burglar). Escape would be possible via the revolving door.