A new service called “TrapCall,”allows cellphone users to unmask the Caller ID on  blocked incoming calls, obtaining the phone number, and in some cases the name and address, of the no-longer-anonymous caller.

The service offered by New Jersey's TelTech systems, the company behind the controversial SpoofCard Caller ID spoofing service, is basically a free unmasking service, and includes the option of blacklisting unwanted callers by phone number. It also allows you to listen to your voicemail over the web. It's currently available to AT&T and T-Mobile subscribers, with support for the other major carriers due within weeks.

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