>I was lucky to get those - guy the same day bought the whole
>lot they had in stock to make helmet lamps for cavers and
>visitors to the glow-worm grottos

One of my work colleagues here in the UK does this as well, though only for
himself. He also uses them on his pushbike - provides enough light around dark
English country lanes to stop you from running into a hedge or off the road. He
tends to use little switch mode regulators from Maxim to up the voltage so he
can run them of a single AA battery. He has a small flashlight that he has
mounted 3 LEDs in instead of the single bulb. The light is brighter than the
bulb, and the battery draw lower!

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