Last year was not a good year for e-mail. In spring 2003, the steady flow of unsolicited and unwanted messages reached a tipping point. According to Postini, a California company whose e-mail– filtering service processes 150 to 200 million messages a day, spam finally accounted for more than half of all e-mail traffic. Then, in August, the SoBig-F virus hit the Net, rapidly spreading via a torrent of e-mail messages. New York–based MessageLabs, which runs a service similar to Postinis, trapped more than a million SoBig messages before the outbreak was 24 hours old, calling it the fastest-spreading e-mail virus on record.
It was the exclamation point on the gradual rise of mass-mailing viruses. This year, MessageLabs says, the ratio of virus-infected messages to other e-mail traffic increased by nearly 85 percent. As if all those SoBig messages werent annoying enough, it was soon apparent that the virus was reprogramming PCs to serve as "open relays," giving spammers still more launchpads for their anonymous attacks. MessageLabs claims that more than 66 percent of all spam is now sent using systems commandeered by SoBig or MiMail, a similar worm.