Maker and experimenter Caleb Kraft over at hackaday.com recently took on the project of making a night light powered by living phosphorescent algae. What he came up with is a set-up that is pretty simple and something that anyone could take on if interested.
Kraft explained the idea behind the project: "My father, an ex navy man, has told me stories of glowing water since I was little. Being a person who was obsessed with all things that light up, this always stuck with me. I saw a headline one day that someone was making an algae-light. Sadly when I clicked on it, the algae was just there to create oxygen. It was a cool idea, but not what I was hoping for. That slight disappointment drove me to create a night light using glowing algae."
As Kraft says, there are three simple steps to creating an algae night light: buy algae, give it a light source for 12 hours during the day and shake it at night (the algae glows when agitated and in its night cycle). He came up with a more complicated way to agitate the algae involving a motor base and a magnet-driven BB that would move through the algae, but it didn't come together the way he hoped.
In the end, he realized that he had great results with just putting it in a large container and shaking it or tapping it to get the glow going. Below you can watch Kraft's video of how he creating this cool living night light and see it in action.