Eton Blackout Buddy H2O
Yes, candles and flashlights can provide light during an emergency — but candles can be fire hazards, and flashlights require you to make sure their batteries are fresh. The Eton Blackout Buddy H2O eliminates both these problems by providing lighting using nothing but water. Thanks to a Magnesium-oxide battery module, this compact light can run for up to 72 hours just by placing it in a small cup of water and adding a little more liquid once a day. And if you can't find water during an emergency, well, odds are you have bigger problems than a lack of lighting.