There was one episode where ina small town cars, machinery like lawn mowers etc., would run around by themselves or start up when no one was around them. Townsfolks were turning on each other, getting into fights, finally shooting at each other. In the end two aliens standing on a hillside; one says to the other, "You see, all you have to do is control their machinery and they take care of the rest".
I think of that every time I open my toolbox...... 
