Here is the (brief) history of the legendary Captain Crunch in his own words …

So, lets go back to the year 1972, when I got a phone call from Denny, a blind kid who turned me onto a toy whistle he got out of a Cap’n Crunch cereal box.With this whistle, it was possible to access the internal trunking mechanism of Ma Bell.
In conjunction with a blue box (A special tone generating device), it was possible to take internal control of Ma Bell’s long distance switching equipment.
Link: Cap’n crunch in cyberspace
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