There’s an inherent dilemma in purchasing a flashlight: The really bright and long-lasting LED models are pretty expensive, and the heavy, cheap traditional ones always seem to be dead just when you need them the most. Good thing it’s possible to build your own superbright, reliable and inexpensive hybrid light.
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Science is reinventing play, from extreme sports to gamification to ridiculous roller coasters to the playgrounds of tomorrow, and this issue is chock full of fun. Also, on a less fun note: Did global warming destroy my hometown?