There are stories of strange devices and items of powers throughout history. Some are devices left over by visiting ancient astronauts, while other have been imbued by the power of the gods, and others still were created by lone inventors struck by unique insights. The difference between artifacts and hidden technology is that artifacts are usually one of a kind and do not necessarily depend on science to function, while technological devices can be mass-produced - or could be mass-produced, if only THEY permitted it.