He also has a post that links to a Wired.com article on caller ID spoofing such as offered by spooftel.com. This service allows you to select any phone number you would like to show up on the Caller ID of someone you call. Besides the obvious prank potential, this might come in handy when you call customer service at a company who's been non-responsive to a good customer like you.
Theoretically (kids don't try this at home) you could use a service like this to find a corporate executive's phone number from a company that has been offering you poor customer service. After you get the CEO's or other high-level exec's number to use as your spoofed caller ID, don't bother calling customer service - they're just poor hacks, instead call someone in low level management that would never have spoken directly to the CEO/executive. Tell them you received a phone call from a customer (you) who has been receiving terrible service from the company. In your most authoritative voice tell them you are holding them personally responsible (whether this makes any sense or not).
Before you actually do something like this you might want to consult an attorney since according to the Wired article the FCC is cracking down on Caller ID spoofing. Some of the websites that offer these services are non-US entities, so that might provide you with some measure of confidence that the FBI won't be knocking on your door.
