[junkman]

Thought about it a few years ago, think similar have been done know, but at least I would have taken the effort to look into a patent. A solar recharged electric lawn mower, you bury a wire around your house like a wireless dog fence, the electric mower just roam around the yard keeping the grass mowed automatically, kind of like a roomba vacuum cleaner. I thought it was a good idea, until the neighbor kids get curious and flip it over, or dogs or something, then you just have a huge lawsuit. I guy I used to work with patented then sold the patent (or at least claims he did) a garage door opener with a carbon monoxide detector that open the door automatically if the level gets high. Said he sold due to liability if it failed.