Jury Rigged

I'm sure the nautically inclined out there will recognise this as the Jury or Masthead Knot but I wonder if anyone has ever actually needed to use it? It is traditionally used in cases where a ships mast has been lost and a temporary one has to be rigged. As I work on a ship which doesn't have sails it is highly unlikely I'll ever need to use it in anger but it's nice to know how to tie one... you never know when it might come in handy! :-)