You better stop talking about it unless you want to force one of 007's colleagues to have to kill you
That 767 was for some Defense Dept. project that has ended. I suppose the special 767 can be modified for a new project in the future.
There was a 757 or 767 on the drawing board with a double deck in the rear (with the tail on top of that). That design was not adopted for the 777. It was called the "Hunchback of Mulkiteo" named after the town next to Everett.