USATODAY.com - Caller ID spoofing becomes all too easy

In the last few years, Caller ID spoofing has become much easier. Millions of people have Internet telephone equipment that can be set to make any number appear on a Caller ID system. And several websites have sprung up to provide Caller ID spoofing services, eliminating the need for any special hardware.
For instance, Spoofcard.com sells a virtual "calling card" for $10 that provides 60 minutes of talk time. The user dials a toll-free number, then keys in the destination number and the Caller ID number to display. The service also provides optional voice scrambling, to make the caller sound like someone of the opposite sex