The Skean Dhu hotel in Aberdeen used to have set-top boxes that, with the use of a swiss army knife, you could open. Inside was a "clicker wheel" with your room number selected. All you had to do was change the number to someone elses room (preferably not one of you own crews !), press "confirm" and you got free movies !! This was quite a few years ago and I think the system was upgraded to stop this sort of thing. Oh how I miss ABZ night-stops !!!!!
Oh yes, then there was the "kettle lead" trick at the hotel in EDI (Post House I think...?) but that's another story !