A very similar thing happened to me, actually. I was living in a townhouse development, where apparently they installed the same remote control ceiling fans in all the master bedrooms. Well, needless to say we had some fun with the neighbor's fan, and we would occasionally go to war, standing by the wall pressing the buttons over and over again. You can change the code for these as well, but from what I understand, the guys living in the room since I left have decided to keep it the way it is.
Just thought you'd like that story.
Chris