LED Light.

-->Over in Crete, and probably at holiday destinations all over the world, you can buy lighters, with LED torches incorporated in them whose intensity is astonishing. You can also buy torches alone that utilize numerous LEDs, and throw out one hell of a beam of light powered by a set of batteries smaller than the collection of LEDs itself. I’ve seen keyrings with these things in, and know that some manufacturers produce them for home lighting. However, they haven’t caught on as yet, because of the ridiculous unit cost. But perhaps they will now:

The researchers have designed a bulb that is three times more energy efficient than today's best offer and can cut lighting bills by 75 per cent. They are made using Gallium Nitride (GaN), a man-made substance used in LEDs (light emitting diodes). It is routinely used in bike lights, mobile phones and camera flashes.

But until now the production costs have been too expensive for widespread use in homes and offices - a single bulb would have cost £20. However, the researchers have found a cheaper technique to help manufacture the bulbs and manufacturers have begun work on production prototypes. The first units could hit shelves within two years. Professor Colin Humphrey, head of the centre, said: "This could well be the holy grail in terms of providing our lighting needs for the future."

The bulbs are 12 times more efficient that conventional tungsten bulbs and three times more efficient than compact fluorescent "energy efficient" bulbs. They can burn for 100,000 hours and they illuminate instantly and can be dimmed, unlike energy efficient bulbs. If they were installed in every home and office the bulbs could cut the proportion of UK electricity used for lights from 20 per cent to 5 per cent a year.