I've flagged an AI-generated add once that promoted a small device that could cool a hot room (many degrees celcius lower, very quickly, for very little energy and very little money and without external components), defying the laws of thermodynamics.

They said they investigated it and concluded it did not break any rules and no actions where taken.

The whole idea behind scam sites marketing is to present an ad that knowledgeable people will find unattractive but gullible people will be lured into. Self selection keeps the based demographic from investigating the scam.

There do exist "evaporative coolers", sometimes called "swamp coolers". The trick is that they require water and raise the humidity of their surroundings. But they tick all the boxes you listed - plenty of delta-t, extremely low power, no external tubes or parts.

It's not magic because it relies on the "fuel" of cool water to evaporate.

I've seen similar ads. For the ones I've seen the device isn't necessarily fake: it's just a swamp cooler. They're cheap and efficient if you're suffering in a dry heat.

ETA: the ads I've seen are still deceptive because they're claiming this is revolutionary new technology, which of course it isn't.

In July there was a BBC article on this, and how they were advertised on Facebook and YouTube.

https://www.bbc.co.uk/news/articles/cj6g41pzy41o

"Lisa, get in here... in this house we obey the laws of thermodynamics!"