I just finished reading throught the 49 pages to make sure I would not repeat...
True story from where I work a few years ago
To a South Eastern Delta feeder (bible belt):
CLX: AAA1234 cleared to ATL .... squawk 0666...
A/C: AAA1234 cannot accept this sqawk
CLX: roger, switch to ground who will give you your code
CLX gets a new code from flight planning and gives the story to GND with a suggestion for a joke
GND: AAA1234 I have your new squawk code
A/C: ready to copy
GND: it's 1313
long pause
CLX to GND: better give it the real one before they leave the plane
GND: seriously, it's 1234
A/C: we're happy it's a joke
I will add on a regular basis stories that happened to me or my collegues... if they are deemed funny