http://www.cnn.com/2002/TECH/ptech/1...net/index.html
Here's a snip:
The e-mail looks harmless enough: A link to a greeting card that appears to be sent by a friend.
But clicking on the link can place porn images on a desktop, download a barrage of x-rated ads, or send similar e-cards to those listed in Outlook's address book.
No downloadable e-mail attachments to install. No infected disks shared. All the user has to do is go to a link.
E-mail marketers -- many of them porn sites -- are increasingly borrowing tactics used by hackers to trick potential customers into seeing their messages, anti-virus experts say. And often, they use Microsoft's ActiveX Controls, which are meant to make Web pages more interactive, to instantly download their unwanted programs.