As file swapping services, such as Kazaa and Napster, surrender to music copyright laws, BT Openworld has found a clever way of using them to its advantage.

BT Openworld Classical, launched yesteday, is a subscription-based service offering a searchable, downloadable catalogue of around 6,000 classical tracks. The fee is £7.99 a month — roughly in line with the amount that music swap site Napster once thought of charging people to use its service ($5).

But where other peer-to-peer sites have struggled to meet copyright laws BT Openworld will not have this problem. Under UK copyright laws, music is free from restrictions 70 years after the artist's death — a drop in the ocean compared to the 175 years that Beethoven (pictured) has been gone.

"Once 70 years has passed then it's free for anyone to use for whatever they want," said Florian Coempel, spokesman at the British Music Rights Association. "If an orchestra or group publish their own edition [of that tune] then their edition will fall under copyright."

"This is the beginning of a series of online music initiatives we will be launching, it just happens that classical music is the first," said a spokesman for the company.

But BT Openworld could be in for a much harder time when it sets up other music sites, according to the Music Publishers Association.

"There is a lot more legal [red] tape, so to say, around new music. Sometimes copyright fees outweigh the benefits of playing the music," said a spokesman at the MPA.