There is an umbrella invention that aims to light your way in the rain. The umbrella is created by Korean designer Sang-Kyun Park. According to the writeup on Yanko Design, the outside canopy has a conductive membrane called PDVF. As rain comes down, the impact generates electrical energy that powers built-in LEDs on the umbrella. The harder the rain hits, the brighter the light to help you see your way. Now that's literally a brilliant idea, but the lights better be waterproof or you'll end up as an electrifying light show.