Given the limitations of other services, FastTrack, a fledgling Dutch company that licenses peer-to-peer, file-sharing software, is poised to take advantage. The 15-month-old company has licensed its technology--which enables the network-based exchange of a variety of file types--to media file-sharing services like KaZaA, MusicCity, and Grokster, and Napster's woes has it licking its chops.

Unlike Napster, which manages file-sharing activity centrally, or Gnutella, which is limited by a ceiling of 100,000 simultaneous users, FastTrack uses a concept it calls "SuperNodes" in which individual users with particularly powerful computing configurations become unwitting servers. These users become virtual nerve centers from which the activities of groups of file-sharing participants are managed, making it possible to support basically unlimited numbers of users without sacrificing speed. Additionally, FastTrack isn't limited to music, giving it a much wider potential reach than Napster. It also enables the swapping of still images, video, software, and documents. And because FastTrack doesn't actually host any services, it pushes liability related to copyright infringement onto its customers and their users.

FastTrack CEO Niklas Zennstrom says he expects the SuperNodes concept to drive demand among companies looking to implement peer-to-peer technology without having to invest in costly networks. "As compared to building a centralized network, they do not need to procure any servers," says Zennstrom.

Webnoize analyst Lee Black says FastTrack has seen explosive growth in the past month, with the average number of simultaneous users logged on to its customers' services increasing from 225,000 to about 400,000. That's nearly 10 times Gnutella's average traffic. But despite FastTrack's location overseas, Black says he wouldn't be surprised to see the Recording Industry Association of American join forces with the International Federation of the Phonographic Industry to mount a legal challenge. He says the irony of the RIAA's successful campaign against Napster is that instead of having to monitor a single, popular file-sharing community, the base of Napster users is now fragmented and thus considerably harder to control. Technology like FastTrack, Black says, is guaranteed to further complicate things.