We had a third line in the office at my Dad's business, and it never got anything BUT wrong numbers for some reason. I knew this for a fact, based on direct experience, because I was the one who normally answered that phone. Accordingly, after awhile whenever it rang I would instantly pick it up....say..."YOU GOT DE WRONG NUMBAH!!!!" in stentorian tones...my best imitation of a mean black gangsta rapper voice...and instantly hang up.

Heh! I've always wished I could have seen the reaction on the other end...

No one ever called back.