I just measured a pair of LEDs "just for fun" and discovered that they're outputting energy. I held one on the LEDs in the sun's direction and the Multimeter went straight up to 10V. I laughed because I had absolutely no clue what's happening inside those things and how...
How is that possible? Are they "solar panels" in a way, because ... how can this be?
Below are two pictures of my "finding":
(I tried plugging an Arduino Mega on the other end to see if it would power on but unfortunately it stayed off)
I also measured the amperage between the two leads, but the only mode that work on my multimeter is the "10A" mode. It stated 0.00(A).