An anonymous reader writes: Verizon Wireless, the nation's largest wireless carrier, is now also a real-time data broker. According to a security researcher at Stanford, Big Red has been adding a unique identifier to web traffic. The purpose of the identifier is advertisement targeting, which is bad enough. But the design of the system also functions as a 'supercookie' for any website that a subscriber visits. "Any website can easily track a user, regardless of cookie blocking and other privacy protections. No relationship with Verizon is required. ...while Verizon offers privacy settings, they don’t prevent sending the X-UIDH header. All they do, seemingly, is prevent Verizon from selling information about a user." Just like they said they would.