"magnet that hooks a snake from the basement to the attic for pulling homeruns..." done that.... Magnet on a string, on a fishing pole, on a string on a fishing pole, throw magnet across drop ceiling, down walls to cathch another string with a washer on it, or another magnet, retrieve lost linemans, stud/screw/nail finder, keep everything in place in the bags, and pouches... I love magnets!
X-ray goggles would be neat! Although I have thought of getting in the GPR market. (Ground Penetrating Radar) Better than X-ray for floors and walls made of concrete....
Anyway, it can be done... Look at these guys.... All started with an idea....
http://www.maxistools.com/ http://www.no-dog.com/ http://www.rack-a-tiers.com/