When my mother in law last came to visit, she mailed ahead a plug-in "purifier" that was supposed to... de-ionize your phone. Or something. There was an LED but she said that it's not supposed to light up. She wanted us to have it plugged in and humming before she got there.

So I took it apart.

Super simple circuit - it was a remote controlled outlet switch. Was eventually able to find what looked like an exact match, sold in a three-pack for like $30. The LED was supposed to light up when it was turned on (with the missing remote). MIL paid like $90 for it from one scammer or another. She was super pissed when it wasn't plugged in when she arrived. Refused to listen to anything either of us had to say on the matter.

She's still patiently waiting for the global currency reset that will make her rich. And/or the cloud ships to come and rescue the faithful.

It's trivially easy to grift the credulous.