Lycos is offering its customers a screensaver that helps to launch distributed denial-of-service attacks on spammers' Web sites.
The controversial move is designed to use the idle processing power of a computer to slow down the response times from spammers' Web sites.
"Lycos has been trying to position itself in the fight against spam," said Wessel Van Rensburg, product manager of communications for Lycos. "It launches tonight in the UK. It aims to use our community to fight spam. It uses idle computer power and sends requests to spam sites."
On its Web site, Lycos, which claims to have an army of more than 66,000 computers, says it has already attacked several Web sites, slowing one down by 85 percent of its operating speed. The software is open to Windows and Mac users.
The company said that when the screensaver is active it displays the location and URL of the sites users' PCs are attacking, and that Lycos decides the Web sites it will attack.
A spokesman for the company said: "This gives Internet users the opportunity to hit spammers where it hurts. Sending spam is not a minor misdemeanour, as spam causes billions of pounds of damage to the economy. This is why we are upping the ante in the fight against those responsible for spam."
But DDoS attacks are illegal in a many countries and some organisations have criticised the move. Steve Linford, director of non-profit anti-spam organisation Spamhaus, has dedicated the last eight years of his life to fighting spammers. He said that Lycos has failed to think the idea through.
"It's irresponsible of Lycos to put its name to it because it lends legitimacy to [DDoS] attacks," said Linford. "You can't break into a thief's house just because he breaks into yours. We don't support this or recommend this practice. Directing traffic is part of the degradation of the Internet we are trying to stop."
On its Web log, security company F-Secure also warned users away from the idea.
In its 'make love not spam' campaign, Lycos entices users to join the zombie army with the following message:
"Are you sick of getting unwanted messages in your inbox? Here's your chance to join the fight against spam as now you too can get involved. Download the Make Love not Spam screensaver - the only screensaver that actively works to stop the spammers - and tell your friends to do the same to spread the love."