It looks like the latest website craze: a site that exposes unfaithful lovers with information provided by the general public. But despite being featured in the national media, the site at www.cheatingscum.com is not the litany of lost love it appears to be. In fact, it has turned out to be an elaborate hoax.

"The site took on a life of its own," explains the site's creator Dan Oliver. As deputy editor of .net magazine, a consumer internet title, Oliver wanted to show how the successful marketing of a website could be done for next to nothing. The site was assembled in a few hours and - apart from an afternoon spent in London with a sandwich board - had an advertising budget of zero. More than 10,000 people visited the site in its first week.

"We'd witnessed a number of high-profile dot.coms crash while a lot of people were saying that you had to plough thousands of pounds into the marketing of your website," says Oliver. "We wanted to show that with a bit of imagination you could do it for nothing."

Oliver collected email addresses of reporters on national newspapers and broadcasters. Next, he created a mailing list, wrote a fake press release and sent it out. Within two hours the site had received a hundred hits. The Mirror, Capital Radio and e-marketing bible Revolution, picked up the story. Not one of them thought the story was a hoax.

For legal reasons the site could not use the dozens of submissions that were now being sent in. Instead, it used pictures of family and friends, and colleagues at .net wrote about the "cheating love rats" themselves.

"None of the people who reported on the site did any research into it. If they had, they would have found out that it was all totally fictitious," says Oliver. "The national media really need to take a look at the way they report internet stories. The tabloids only seem to be interested in the net in a negative way. We just wanted to play them at their own game."

CheatingScum is an example of viral marketing: a cheap and imaginative way for companies to get their message across. Viral marketing depends on internet users helping to promote a product or service for somebody else.

"For small companies, viral marketing is now the most important way to market your website," claims Oliver. "When you employ viral techniques you are targeting people who are already connected to the internet. It's all very good placing a billboard ad in the street, but there is little guarantee that the people are going to remember to log on."

For CheatingScum to work virally, Oliver had to persuade visitors to the site to tell others about it. "This was the best marketing tool we used," says Oliver. "Because one in five people who visited us would actually refer it to a friend. When that carries on you get a kind of daisy chain effect and your hits can go through the roof."

And it is not just small companies who are employing viral marketing techniques. Earlier this month, Ford launched a viral marketing football game to support its sponsorship of the Uefa Champions League. Viral marketing is also being used by Coca-Cola, Nestlé and by the producers of the new Spielberg movie A.I. Even the main political parties are adopting viral techniques in their election campaigns.

But with the likes of Ford now adopting viral techniques, how long will the small players be able to keep their edge? "The most effective viral marketing is a bit tongue-in-cheek and irreverent," says Oliver. "I don't think Ford and Coca-Cola want to be associated with that."