Your home and office computers are probably protected by antivirus programs and firewalls. But what about your new cell phone? The latest "smart phones" let you read e-mail, open attachments, and download games and other programs. Just imagine if a virus slipped through that made toll calls to 1-900 numbers in the middle of the night. With phone spam already here (see "Spam to Go," TR April 2004), industry experts suspect phone viruses are bound to come calling soon.

Anticipating the arrival of phone viruses, security software companies are starting to develop dedicated antivirus products. F-Secure of Helsinki, Finland, says that over the past year or so it installed virus detection systems in the networks of nine cell-phone service providers. This year, the company says, it will start selling antivirus protection software for phones themselves. "We don't want to wait for [an attack] to happen," says Mikko Hypponen, director of antivirus research at F-Secure. In most respects, the company's antivirus program works the same way as the one on your computer, examining incoming e-mails and files for known viruslike code patterns and behavior. But it's customized to work with the far smaller memory and lower processing power of a typical phone.