A few months ago I was in Pittsburgh visiting a friend. While looking over his garden, I heard a ruckus and saw a fire coming from a car parked in the parking lot of a drivethru restaurant. You can see the video here. The fire was the result of the driver throwing his change into his ash tray which was missing the lighter. Evidently a dime got stuck in the hole where the lighter would normally be. The car was totalled.
Today, I was checking smoke detectors in the house and after replacing a weak battery, placed the old battery into my front pocket. Later this evening, all of a sudden I felt a burning sensation. Evidently the battery terminals had come in contact with some change in my pocket. Man, that battery was hot hot hot.