For some of us is started with Nancy Drew mystery novel, where the fireplace piveted into a hidden entrance. For others it was the "Clue" boardgame with the secret passage linking the Kitchen and the Conservatory. However it began, most of us have been fascinated by the concept of a secret room since childhood.
Well, if you have the budget for it, you could have your very own hidden passage or room. In fact, according to this article it's becoming more and more common. I'm in!