And RBCP- *57 and *69 DON'T work on cell phones. You can still be traced but the star codes won't work. I have just tried. You will get an error message. Once again that is only here in OC. Try doing it at your house.
That's not entirely accurate.
*69 won't work on any phone that doesn't pass the number via Caller ID - i.e. *67 blocks, or other restricted numbers (such as unpublished). It doesn't matter if it's a cellphone or not. My cell number is not "restricted". If I call someone, they can *69 my cell. This has been verified with AT&T/Cingular, Verizon, Qwest, Sprint, Nextel, Verizon and T-Mobile. I've had each and every one of those carriers within the last 2-3 years, for personal or business.
*57 is potentially trickier when a cellular phone has been blocked, but it's not impossible. The human element of tracking/tracing gets involved here.
Your cellular carrier knows EVERYONE you call - it's a matter of billing/record keeping. If a person *57's after receiving a call, their carrier may not be able to pull up that number, but they can flag the last call based on where it came from, i.e. a Verizon POP (the point at which the airwaves meet the copper). The called carrier (the person that was pranked) knows the origination time of the call, the duration of the call, and the termination time of the call. They know the incoming carrier (in our example, Verizon). With a police warrant/request, they can contact the carrier that made the call, give them the origination, duration and termination information (SHUN SHUN SHUN!), and the cellular carrier can match that with your outgoing call records, and, presto, the police have a match.
At my prior employer, the exact thing happened. We had an employee who was making threatening phone calls to his ex-girlfriend's new boyfriend and his family. Qwest couldn't get the actual cell number, but they knew that it was coming from a Nextel phone, and then changed to a Verizon phone (we changed carriers mid-harrassment cycle). They correlated information with both carriers, and that produced a match to one of our corporate cellphones. Obviously, we know who was issued that phone, and HR had his final paycheck ready for him when the police came to question him.
Even when a *57 errors out (you get the error message intercept), it still flags all the pertinent information in the system.
If you're REALLY worried about anonymity, don't make calls from your house, or anything that might be papered to you. Prepaid calling cards from a cellphone, beige box, whatever...