In "Exploding the Phone," Phil Lapsley writes an entertaining and educational history of the people who hacked the original phone networks. Lapsley talked to CNET about his book.
Imagine a day when it cost an arm and a leg to use the phone, especially for long-distance calls. Then imagine that buried deep within the telephone network infrastructure was a flaw -- a hole that allowed those who were aware of it, and capable of exploiting it, to make all the free calls they want.

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