It would be really cool to take one of those cars, and put like an extremely deepseeking coil on it! Or gear it for underwater and make it run along the bottom of the ocean!
I actually invented that, but mine digs it up and classifies it as Junque or treasure , In my mind, But it can and obviously has been done. Whats next??
Here is the Treasure Finding Car I built. No metal detecting capabilities, but it has a wireless infra-red camera, and a range (line-of-sight) of about 3000 feet (about two-hundred underground). I mostly use it for reconnoitering caves and mineshafts, before I walk in (don't like surprise face-to-face meetings with Cougars or Badgers).