The style and purpose of viruses runs the gamut. The Sophos antivirus company offers these brief synopses. For an exhaustive list of virus explanations, visit www.sophos.com/virusinfo/analyses. See Sophos and virus. Love Letter The fastest spreading virus in history appears to have been written by a resident of Manila in the Philippines. Sent via e-mail in May 2000 with "I LOVE YOU" in the subject field, it replicated itself to everyone in the user's Outlook address book and then destroyed local files. Love Letter forced numerous organizations to shut down their e-mail systems, as computer users were far too willing to let love into their lives. CIH (a.k.a. Chernobyl) This virus, written by Taiwanese student Chen Ing-Hau, triggers on the anniversary of the Chernobyl meltdown. The virus attacks the BIOS chip on the computer, effectively paralyzing your entire PC. Melissa David L. Smith, 31, named his virus after a stripper he knew in Florida. His virus created chaos in March 1999 when it spread around the world in a day, clogging up e-mail systems and inserting quotes from Bart Simpson into documents. Smith admitted causing over USD $80 million worth of damage to North American businesses. Nimda Meaning "admin" spelled backwards and launched in September 2001, this denial-of-service worm flooded hard disks on more than a million clients and servers on the Internet. Perhaps the most complex virus ever created, it used various flaws in Microsoft's Web server and browser software to unleash itself without the user's knowledge. See Nimda. 911 No relation to 9/11 in New York, the 911 virus was seen in Houston, Texas. It takes over the computer modem and dials emergency services. Kylie This virus, fortunately rarely encountered, plays the pint-sized Australian popster's song "Never too late" through your PC speaker. SMEG "Smoke me a kipper, I'll be back for breakfast! Unfortunately most of your data won't!" The Simulated Metamorphic Encryption Generator viruses, written by the Black Baron, trashed hard disks up and down the country in the mid-1990s. The author, Christopher Pile, was a fan of the Red Dwarf series and ended up being sentenced to 18 months in prison. Nuclear This word macro virus adds a paragraph to the end of every document you print protesting against French nuclear testing in the South Pacific. Coffeeshop Written by the Trident virus writing gang based in the Netherlands, the Coffeeshop virus displays a large cannabis leaf on the screen of your PC and urges the government to legalize marijuana. Casino Casino was written on the island of Malta and plays Russian Roulette with your hard disk. If you get the number wrong, you lose everything.