Hovering around a public power outlet - at an airport, coffee shop, book store, etc - waiting for another person to unplug their laptop or phone so you can plug in and charge up.
"Yeah, I'm power lurking at Barnes and Noble. My laptop battery is almost toast. There's one outlet but a dude is using it for his phone and laptop. I gotta hover and jump on it as soon as he splits."
Entering a livestream and telling the others that you're going to lurk, but joining the same game session as the streamer.
Happens in games that use simple codes to join servers, like Jackbox Party Pack games.
"Yeah, he was totally Power Lurking in that game of Quiplash."