Danny Stein, whose private equity firm owns eMusic, thinks the future of the business is to move away from the ownership model entirely. With ubiquitous broadband, both wired and wireless, more consumers will turn to the celestial jukebox of music services that offer every track ever made, playable on demand. Some of those tracks will be free to listeners and advertising-supported, like radio. Others, like eMusic and Rhapsody, will be subscription services. Today, digital music economics are dominated by the iPod, with its notion of a paid-up library of personal tracks. But as the networks improve, the comparative economic advantages of unlimited streamed music, either financed by advertising or a flat fee (infinite choice for $9.99 a month), may shift the market that way. And drive another nail in the coffin of the retail music model.