Napster rival switches to ad-based client

Reports of a declining trade in MP3 files following the legal suit that has forced Napster to try to stop its users sharing copyright-protected files have ignored the migration of users to other services based on Napster's technology.

These services, running technology cloned from Napster's centralized servers, known as OpenNap servers, have blossomed in recent months. One of the most popular, belonging to MusicCity.com and functional up until Sunday, typically offered in excess of 20TB of data. At their peak in popularity Napster's official servers offered around 12TB.

On Sunday evening, however, all trading through MusicCity's servers was halted and all users were sent a pop-up message telling them to download a new client, called Morpheus. MusicCity also appears to have attracted a significant number of ex-Napster users to this new client, claiming to already have over 27,000 users on its first day.

The new client is more akin to Gnutella than Napster in that it has no centralized server and instead lets files flow directly between users, a technique referred to as peer-to-peer. Also like Gnutella, it is designed to enable users to share all kinds of media, not just MP3 files.

It remains unclear, however, how MusicCity intends to make its new technology pay for itself, whether it plans to charge users, and how it may try to fend off attention from the Recording Industry Association of America (RIAA), which has caused Napster so much strife.

A spokesman for MusicCity, who describes the company as a startup, refused to be drawn on any of these points. He said that the firm's position would be made clear in coming weeks, with the launch of another Morpheus client. He also said that the fate of MusicCity's OpenNap servers was currently "up in the air".

He did not rule out the possibility that source code behind the technology might be published, allowing a wider community of programmers to contribute to development of its usability and functionality.