It was not that terribly long ago that people spoke quickly during their phones calls due to the expense of long distance calls. Phone Phreaks found hacks to make free phone calls and scared the heck out of AT&T.
It Exploding the Phone: The Untold Story of the Teenagers and Outlaws who Hacked Ma Bell, author Phil Lapsley tells the story of many of the original phone phreaks, including the most famous of them all John Draper; better known as Captain Crunch.
I read the first 50 pages and this is a most interesting book. Lapsley knows how to tell a great story.
Full review to follow.