Google users experienced problems whether their own computer was infected or not. This is because the virus struck at the Google's own servers, potentially slowing it down for non-infected computers using it by bombarding the search engine with requests until its servers couldn't cope.

The attack was directed at Lycos, Altavista, and Yahoo too. In Google's case, the attack received most publicity since it coincided with the company's long-awaited announcement on the value of its public flotation.

"Google's down!?!?!?!?" wrote one Internet chatroom wag, "Forgive me while I stock up on water and ammunition."

This new variant of the MyDoom "worm" - MyDoom.O - spreads by e-mail. When it infects one computer it not only looks for e-mail addresses on that computer, it looks for them via search engines as well - hence the performance problems, as Google, Lycos, Altavista, and Yahoo began receiving many more requests for information more than they normally get as the virus kept on and on saying "Give me more e-mail addresses." 

Some of the MyDoom.O subject lines to look out for:

"Delivery failed", "Message could not be delivered", "Mail System Error - Returned Mail", "Delivery reports about your e-mail", "Returned mail: see transcript for details", "Returned mail: Data format error instruction", "MAILER-DAEMON", "Mail Administrator", "Automatic Email Delivery Software", "Post Office", "The Post Office", "Bounced mail", "Returned mail", and "Mail Delivery Subsystem".

One curiosity is that, if you want to find another search engine to bookmark as a back up should the MyDoom.O virus attack again, and happen to use Google for your search-engine search...it doesn't return Google at the top of the list. A very modest approach, for a company that may shortly be valued at over $30 billion.

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