Madonna's web stunt prompts rash of remixes

You'd think Madonna would have learnt by now: it never pays to annoy the fans, especially on the internet. An attempt by the singer and her record company to embarrass people downloading illegal free copies of her album – by replacing them with a brief message from Madonna, saying "What the f*** do you think you're doing?" – has instead sparked a remix bonanza, with online DJs creating dozens of brand new tracks using her words as a sample.

To complicate matters for the music giant Warner Bros, which hired a company to upload the "spoofed" tracks, it's not clear whether the star could claim copyright if anyone released a single including the file – because she would have no way to prove it is her speaking.

That would mean that if any of the remixes does become a hit, Warner Bros and Madonna would be unable to claim any royalties – unlike a number of other artists over the years, including Suzanne Vega and Gary Numan, who have seen unexpected paydays when underground remixes of their work have suddenly become popular.

The remixes are being collected at a site called the "Madonna Remix Project", owned by a pair of internet users. One, known only as "irixx", says: "When I heard the self-righteous attempts of our lady of pop to inspire repentance in the hearts of guilt- ridden file sharers, I could not help but laugh. the crystal clear sample was a gift horse that i could not look in the mouth."

The "spoofed" files were designed to appear as if they were compressed versions of the songs from Madonna's American Life album, released last month.

They were put on file-sharing networks in the US, where millions of people swap music online free over high-speed connections, despite record companies' anger and attempts to stop the practice.