Radiohead's record company have teamed up with a Napster-style song swap site to promote their new album Kid A.

As the music industry tries to shut down the popular song-swap service Napster, Radiohead's US label, Capitol Records, has joined forces with Aimster, another music sharing program, to give fans a preview of the new album, which is out now in Europe and on Tuesday in the US and Canada.

Aimster, which hosts Capitol's Radiohead promotion for two days, ending at midnight on Tuesday, may be able to avoid copyright infringement suits because it only allows friends to share files with each other.

Napster, however, whose estimated 25m users can download music from anybody else on the service, is being sued by the Recording Industry Association of America (RIAA) - which includes Capitol's parent company EMI.

Previews

Radiohead have welcomed the possibilities afforded by digitally distributing music online.

Fans have been able to preview Kid A on the Capitol Records website, and for a limited time on a number of other sites. including BBC Radio 1 in the UK.

MP3 files of live recordings have been distributed with the band's backing for some time but the band's record company did everything they could to prevent the early appearance of tracks from the album on Napster.

"We played in Barcelona and the next day the entire performance was up on Napster. Three weeks later when we got to play in Israel the audience knew the words to all the new songs and it was wonderful," Radiohead bassist Colin Greenwood told the BBC's Newsnight programme in July.

Piggy-backing

Aimster, which uses the popular AOL Instant Messaging software, uses a Napster-style browser to locate and download compact MP3 files.

Messaging software is used by millions of people to instantaneously send messages to groups of friends on "buddy lists" who are all online at the same time.

Aimster spokesman Johnny Deep believes the service is less likely to fall foul of record companies.

"We firmly believe that instant sharing is the killer application on the internet," he said.

Analysts believe Aimster may provide a solution to record companies' desire to sell music online.

Jonathan Potter, executive director of the US Digital Media Association, said: "Aimster appears to be more a manageable and limited form of file-sharing in terms of distribution.

"It doesn't surprise me that copyright owners are more comfortable with this sort of application."