Anyone who goes running at night probably knows the importance of having a light on you — not just so you can see where you're going, but so others (like cars) can see you. The Million Mile Light is meant for just this situation, but one thing you won't have to worry about is keeping its battery fresh — it's powered by the motion of your run. Every step you take will make the pair of bulbs blink brightly.
A "tiny, silent, kinetic engine," as the creators put it in their Kickstarter pitch, harvests the energy from the light being jostled up and down. It's not exactly futuristic — this kind of tech has existed for years — but it is made more useful by the fact that modern LEDs are so small and use so little power.
If it's really dark you'll probably want a traditionally powered flashlight to shine on the road ahead, but the Million Mile Light looks like a good secondary safety measure. Right now you can pre-order one for under $20 — the devices should ship early next year.