The Associated Press reports on the beta website ThePudding.com, which is offering users "free" voice over IP (VoIP) calls, with an invasive catch -- it uses voice-recognition software to serve you ads based on the conversation you're having. In some ways, it can be likened to Google scanning your Gmail messages for keywords used to send you targeted advertisements.

Having a computer sift through your VoIP call is eerie, and unfortunately, the reach of voice-recognition-seeded advertising may not be limited to ThePudding.com's site. ThePudding.com's operator, Pudding Media, seeks to license its speech-recognition capabilities to other service providers, including mobile carriers and Internet telephony services. Imagine a scenario in which your own phone company licenses the Pudding Media platform and uses it to mine your calls for valuable personal information. They could use that information within the conglomerate to sell you other goods and services, or they could turn around and sell that information to the highest bidder -- either way, your "private" conversations become a commodity.

Perhaps the most chilling implication of this "service" is its potential impact on your constitutional right to privacy in your phone calls. Fourth Amendment protections against government eavesdropping rely on your having a "reasonable expectation of privacy" in your calls, something you'll arguably be trading away by using ThePudding.com's VoIP service. The government can and likely will argue -- as it has argued when it comes to your Gmail, in the case of U.S. v. Warshak -- that allowing a company to scan your communications for ad-serving purposes eliminates any Fourth Amendment privacy protections in those communications. Far from being "free", you may be paying for ThePudding.com's service with your constitutional rights.