Quoted from pezpunk:In a private residence most people keep them off unless you are having a party or are playing them yourself.
That said, you're not going to damage anything leaving them on for hours -- they were made to do that. It's just a waste of electricity to leave them on for nobody, though.
Yeah, although I've been guilty of leaving mine on at night just so I can look over and say "oooooh."
Yeah, I know. Geeky.