Criminals are now using VoIP (Voice over IP) technology to fool caller ID systems by spoofing phone numbers. This could allow fraudsters to impersonate your bank or other financial institutions by spoofing their phone number. Then try to persuade you into revealing your personal information to commit fraud or identity theft.
Debt collectors and private investigators are also using this technology to get people to answer their phones. Then there is the threat of SPIT (SPam over Internet Telephony). This is where telemarketers could use VoIP to send a huge numbers of voice messages to consumers.
This just mean that we will have to be that much more careful about giving out any personal information over the telephone or trusting the caller ID displays.