A new computer virus disguised as a link to a website with pictures of a party has appeared.

While the e-mail worm MyParty is not proving nearly as devastating as it predecessors Nimda and Kournikova, it is interesting because it uses a new psychological tactic to fool computer users.

The malicious program is the first to use the .com extension in an attempt to fool users to open it.

"It seems as if it comes from mates and the attachment looks like a web address so could persuade otherwise wary users to click," said consultant at anti-virus firm Sophos, Graham Cluley.

The e-mail carries the subject line "new photos from my party", and pretends to direct users to a Yahoo website containing photographs of a friend's party.

Psychological tricks

A message in the body of the e-mail reads: "Hello! My party... It was absolutely amazing! I have attached my web page with new photos! If you can please make color prints of my photos. Thanks!"

If opened, the worm sends a copy of itself to every contact in the Windows address book. Despite initial concerns, the MyParty virus seems to be being contained with only a few thousand reports so far.

MyParty is the latest in a series of so-called socially engineered viruses that use psychological tricks to get clicks.

The infamous Kournikova worm promised users a picture of the Russian tennis player.