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Ok, I've created a php function in the page template for my blog. It implements a function that takes the name of the source image as an argument, and depending on what directory it was invoked from, puts the correct pathname into the
So...anyway. I was recently shopping for aircraft headsets, and there was a neat emergency flashlight advertised on the front page of one of the sites I looked at. It doesn't have batteries in the conventional sense. The main barrel of the flashlight is hollow, with a couple of coils of magnet (very fine) wire around two spools. A tube goes through the middle of the spools, in which is a small magnet. When the shake the flashlight, the magnet slides from one end to the other and back, passing through the coils on the way. The changing magnetic field due to the moving magnet induces voltage and thus current in the coils, which is tapped to charge the flashlight. I assume the actual energy storage is capacitive.
It has a cool blue light (LED I think). It'scalled an "LED Shakelight".