Patently Absurd: Staying ahead of the car thieves

This is the first in an occasional series on odd inventions, based on designs, both ancient and modern, submitted to the Patents Office.

With car theft and unauthorised entry into cars (according to Home Office figures) rising by 52 per cent between 1980 and 1990, car security devices have formed one of the fastest growing areas for patent applications. Alarm systems and steering column locks are the most common, and there is even a combination lock device to disconnect the steering wheel from the column entirely, but nothing has quite the simplicity or elegance of patent application GB2262376 submitted by Anthony Pitchers.

Mr Pitchers' design is for a dummy head which can be fitted on to the back seat of a car to create the illusion of the car's being occupied. While deterring thieves, it may also provide reassurance to anyone feeling vulnerable if they have to drive home alone at night. The inventor also envisages a range of dummy heads in the likeness of famous politicians. He suggests that such a device could provide the opportunity for a driver to release the stress felt in traffic jams by abusing it 'physically and verbally'.

British patent application GB2130179A (published in 1984) clearly demonstrates that it is not only collectors who are fascinated by eggs and their cups. It looks like something between a conventional egg-carton and yogurt-pots, but Mr W N H Johnson's invention is a sophisticated device to satisfy even the most fastidious soft-boiled egg aficionado.

Made of polypropylene, the cups are designed to withstand boiling water so may be placed in the pan complete with egg. Boiling water enters through holes in its base and cooks the egg. Now comes the clever part: the lid of the egg container is impregnated with chemicals similar to those in disposable thermometers.

After two minutes' boiling, the lid turns yellow, after three minutes, green, and after four minutes, blue. Drain the water, remove the lid and you have an egg, perfectly cooked to taste. And the polypropylene container, still in good condition, may take its place in your egg-cup collection.

Compiled from information supplied by the British Library Science Reference and Information Service (071-323 7919).