Battery-free Game Boy (2020)
When I was a kid I had a toy electronics kit and one of the circuits was an AM radio that worked without batteries. A normal radio station signal is strong enough to drive a pair of earbuds without any additional power. Since then I've always wondered if you could harvest that same radio energy to power other things without batteries, maybe even a Game Boy. There's electromagnetic radiation in the air all around us. And I'm sure you could build a Game Boy using today's tech that's much more power efficient than the ones from the 90s.