Online marketers are combining the power of instant messaging with that of peer-to-peer networks such as Napster to create a new wave of Web advertising that some critics call more invasive than spam. By signing on to file-swapping networks, people may expose their instant messaging handles and entertainment tastes to the world. That combination offers a potent platform for lurking advertisers, who are ready to risk annoying millions of Web surfers for the chance to appeal to a handful of receptive music fans. "It's a chilling thought... The songs that you make visible to the world on Napster say a lot about you," said Jason Catlett, president of antispam group Junkbusters. "Many people don't realise that when they're using these P2P services they are becoming publishers of their personal collections -- it's like putting your CD collection in the window fronting the street." For now, major online advertising networks including DoubleClick and Engage have stayed on the sidelines of IM marketing. But other grassroots marketers and online ad networks are aggressively tuning into the affinities of consumers, scavenging the pseudonyms of people who like a particular artist and then inviting them via IM to buy an album or visit the artist's home page. Illustrating the heft of marketing to come, online advertising agency L90 this week inked a deal with peer-to-peer network Aimster in one of the first exclusive partnerships to promote goods to consumers via instant messaging. ADD Marketing and Big Champagne, both newcomers to the Web, are capitalising on the intimacy of file-sharing systems by hitting up Napster and Gnutella users to visit artist home pages or sign up for various contests based on the artists the person collects. Los Angeles-based Big Champagne recently pushed an acoustic version of an Aimee Mann track, off her new album, to fans of the artist, garnering 20 percent response rates from fans, company co-founder Eric Garland said. Such tactics could represent the next frontier in the fight against spam, or unsolicited email, on the Net. Because many consumers sign on to peer-to-peer systems with no idea that they're publicising their music tastes to the world, for example, industry watchers say this makes them sitting ducks to marketers, who can for the first time assemble elaborate data on consumer preferences on movies, music, software and whatever else is shared. "Marketers will scavenge for any personal information on which they can target you," said Catlett. "But unsolicited instant messaging is the same morally as spam -- marketers shouldn't do it, and they're going to get a huge push-back if they try." ADD, which declined to name any of its "less than a handful" of music industry clients or detail pricing, said interest is rising in such marketing efforts after only a couple of months of them being offered. Matt Wexler, online marketing manager for Los Angeles-based ADD, said that although consumers it contacts haven't agreed, or "opted in," to receive promotions, it carefully targets people based on their music tastes. "People will always disagree with what you're doing, but people are definitely open to getting info that helps," Wexler said. In addition, some IM services provide filters for any message from a source that is not on a "buddy list" of shared usernames, meaning advertisers might not have direct access to their targets. Yahoo! Instant Messenger, for example, asks members if they want to chat with an unknown individual before opening a dialogue box. Via Aimster, L90 will peer into the hard drives of people to see what kind of music they're listening to, then send instant message promotions via Aimster's buddy lists, which are compatible to programs including AOL Time Warner's AOL Instant Messenger and ICQ, Microsoft's MSN and Yahoo. Although online advertising schemes such as spam have long survived the enmity of consumers, analysts predict IM marketing will face a bitter backlash. Jim Nail, online advertising analyst with Forrester Research, said that although advertisers cannot actually see private discussions over instant messenger, popping open a chat box on someone's computer screen is similar to interrupting an actual conversation, "This is a really bad idea because instant messaging physically is like a private conversation. This is like you're talking with your boyfriend over the phone and 1-800-Flowers jumps in and says 'I see you're having an argument, why don't you buy some flowers?'" he said. Even some IM marketing pioneers said the long-term viability of pushing ads through peer-to-peer networks faces some serious hurdles. "The instant messaging marketing is in its infancy now, but its life span will be short," said Big Champagne's Garland, asserting that the company is only dabbling in this form of marketing while its primary focus is online market research. Garland called the Aimee Mann promotion a "stunt" because "instant messaging is such a powerful communication tool that it very quickly devolves into spam. It is going to have to be opt-in." Backers of the marketing technique will have a chance to gauge consumer response next week. Johnny Deep, chief executive of Aimster, said that IM campaigns on Aimster will start as soon as Monday and may include such clients as Aerosmith, Microsoft and Columbia Tristar. One example of a potential promotion would be sending an Aerosmith music clip to members of the band's Aimster fan club. Although joining the club doesn't explicitly create an agreement to accept such messages, Deep said, membership implies that receiving that kind of targeted promotion would be OK. "Essentially it's the next wave of commercialisation of the Net," Deep said. "Instant messaging is the delivery vehicle for everything in the same way the Web used to be the delivery vehicle. Now we're using IM for everything, for MP3s, sending movie trailers, software, text." This is so much more effective than banner ads and email because it can be tied to actual results, said Deep, who said that marketers pay by the number of responses to any given promotion. "The risk in this case is to the advertiser. It's so easy for consumers to get off a buddy list that [marketers] will have to be careful of what they send," he said. Deep added, however, that because Aimster is an encrypted network, its members are not as susceptible to marketers as they may be on Napster and other open file-sharing communities. Because the record industry historically hasn't had great information about what motivates people to buy a record, file-sharing networks such as Napster are also gold mines to market researchers. The beauty of peer-to-peer file sharing is that it's an anonymous community, Garland said, and marketers can look at all this activity, ie what content, what films, what songs, what homework assignments are moving where. Big Champagne and others can look at what songs are most popular off any given album and create elaborate profiles on fan segments. "There's a tremendous amount of trend data and info about tastes that's never been available before," Garland said. "But there's a lot of kinetic energy there that almost immediately lends itself to abuse. These are great communities; they don't have to tolerate unwanted marketing." Have your say instantly, and see what others have said. Click on the TalkBack button and go to the ZDNet News forum. 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