Ringtones have proved to be a surprise source of revenue for mobile operators. But like moviemakers who squeeze every drop of blood out of a box office hit with as many sequels as the market can stomach, operators are going to the ringtone well one more time--this time in reverse. Ringback tones allow mobile users to express their creative side by replacing the ring callers traditionally hear while waiting for an answer with music. Another billion dollars in unexpected revenue would be great for operators. However, operators should watch their minutes on the other end. The revenue they might gain initially by selling ringback tones will surely be lost when callers hang up without leaving a message because they can’t stand to hear Ashlee Simpson pretend to be a singer, or a tone-deaf Rod Stewart pretend to be Frank Sinatra. People’s choice in music can be as polarizing as politics and religion. And folks will soon tire of hearing someone else’s personal preferences being shoved down their throat, or in this case, into their ears. Besides, the whole business model is backwards. Anyone who receives 20 calls per day or more and gives callers a little taste of Beyonce Knowles’ latest hit should be compensated. It’s the equivalent of paying for and wearing branded clothes that advertise their designer (which people do, for some goofy reason.) Now, if callers have a video screen and were to get pictures of Beyonce to peruse, in addition to the music, while they’re waiting, that could be compensation enough.