Ever drive behind an ambulance and notice the chains hanging from the rear axel? I’ve always wondered what those were for and today listening to CarTalk they suggested to a guy who was complaining about being shocked by his car to use a ground strap or chains that would drag on the ground to…ground the car. For ambulances, I would bet that being at ground potential is importand for their instruments (EKG?) or perhaps they just don’t want to shock people. Interesting.