But this wasn’t information that would lead my pursuers anywhere. To provide an extra layer of protection, I had previously set up what I call a "cut-out number." The first part of this involved hacking into a phone company switch, finding an unused phone number, and adding call forwarding to the line. Then I set a different billing number in the switch so any calls placed from that number would appear to be originating from the billing number rather than the actual number. Why? I had discovered a flaw in the switch software: it would sometimes report not the actual phone number that a call was originating from, but the billing number. So if phone company techs tried to trace some of my calls, they might not immediately discover my cut-out number—the number I was routing my calls through—but instead would come up with a phone number assigned to some random customer I chose. I knew that some switch technicians were not even aware that a trace might report the billing number, which gave me an extraordinary extra level of protection. In any case, in my experience, the phone companies never caught on to my using a cut-out number to make it harder to trace where my calls were originating from, because it never occurred to them that someone might have hacked into their switch.