A still in-development company called Bopaboo received a great deal of attention - mostly unwanted - after a story in The Guardian on Dec. 3 exposed its plans to create a digital music service that focused on selling "used" MP3s. In an interview with Billboard, CEO Alex Meshkin talked about how Bopaboo will approach selling music and explained how the service will work.

Members will be able to sell any DRM-free digital song they have in their library by uploading the tracks and setting a price between 25-99 cents. Bopaboo keeps 20% of each transaction, and the rest goes to participating license holders.

There are some restrictions. Each used MP3 can only be sold once by any one user. After a user sells a track, the system then bars that user from selling that same track again. And the proceeds from sold tracks can then only be used as credits to buy new music from the site. The credits can't be used to buy other used MP3s.

The service's terms of service will request that users delete any music sold via the system from their library under a sort of "gentleman's agreement" or honor code, but it will not enforce that request in any way.

While positioned primarily as a used MP3 marketplace, Bopaboo will also have music provided directly from participating labels so there is no gap in the available catalog, just like any other digital retailer. Meshkin says he is in "positive" discussions with several major and indie labels, and hopes to have a broad selection of tracks from both before going live.

Currently in private beta, the company hopes to launch sometime next year.