Think about anything with a heating element in it (if electric): * Water heater * Dryer * Oven/range * Microwave * Coffee pot * Toaster [oven] Those can get "s

Think about anything with a heating element in it (if electric): * Water heater * Dryer * Oven/range * Microwave * Coffee pot * Toaster [oven] Those can get "spiky" depending on who is in the house.