I'm a stickler for unplugging and shutting off anything electrical at night, but I'm particularly fussy when it comes to the lights. Whenever I'm not using a light I turn it off, and whenever I catch somebody else not using a light I turn it off as well. I even do this in other homes, where I have no stake whatsoever in the electrical bill. What about the rest of you? Are you driven nuts by the thought of a light left on, or do you not care? And if you do care, do you notice an appreciable difference in your electrical bills each month?