YAWV (Yet Another Windows Virus)
From the BBC News report
Computer virus insults victims
Security experts are warning computer users to be on the look-out for an insulting worm that can serious harm a PC. Known as Winevar, the worm is spreading via e-mail as an attachment that infects computers running Windows. Winevar has a particularly rude tag, displaying the message: "Make a fool of oneself: What a foolish thing you've done!"
Another side effect of the virus is its ability to change a computer's settings to create an imaginary file extension ".ceo". Any future viruses sent with this file extension will be automatically run on the computer. "It is quite amusing that in the post-Enron world we find that CEOs can be dangerous to your PC," said Mr Cluley [Graham Cluley, Senior Technology Consultant for Sophos].
Go on, update the virus definition files again. Why do people write these things? There are better coding challenges than vandalism. The challenge is to fix the holes in Windows and put up some decent defences like hardware and software firewalls. Writing virii is mindless destruction, pathetic little kids throwing a brick through a window just because they found a good sized brick.