Instructables user Randofo has created a tutorial for his ingeniously perverse candle-powered electric candle. As the name implies, it's an electric candle whose power comes from the heat given off by a real candle.
I have been thinking a lot lately about being more prepared, and what supplies we should have on hand for when the 'big one' hits. After prioritizing the three most obvious things to have in a severe emergency - water, food, and a fair-sized crowbar - it came down to figuring out what else one needs to survive. It did not take me very long to conclude this item was electric lighting. I use that all the time. How can I live without that?
After assessing the problem, it became apparent to me that after a few days of constant lighting, all of my batteries will be dead. This means that either I need rechargeable batteries, or a way to generate electricity without them. Not needing batteries to begin with seemed most sensible to me. I explored different options and finally figured out a low-cost, long-term, and portable, method to keep my electric candles lit. I am going to use heat generated by tea lights. The nice thing about this solution is that they are dirt cheap, small, and will last forever. You can buy about 1,000,000 tea lights at Ikea for $1.99. With a fair-sized stock of small candles, I can keep my electric candle lit indefinitely. Thanks to my candle-powered electric candle, I know that I will never be left in the dark.
I write books. My latest is a YA science fiction novel called Homeland (it's the sequel to Little Brother). More books: Rapture of the Nerds (a novel, with Charlie Stross); With a Little Help (short stories); and The Great Big Beautiful Tomorrow (novella and nonfic). I speak all over the place and I tweet and tumble, too.