Google Developing 'Ringback Advertising' For Google Voice

Note: Headnote: The days of the dulcet "ringback tone" -- the sound heard when waiting for a call to go through -- may be numbered. Google is developing a system to sell audio ads as ringback tones.

Google has updated a patent application filed last year for "ringback advertising," a form of audio advertising that appears to be intended to work with the company's Google Voice service.

Audio ads, the patent application says, may unnecessarily annoy consumers. But providing audio ads during a time otherwise used to play a ringback tone may allow advertising without annoyance "because the consumer would have to otherwise listen to...