The term "wireless security" may seem a contradiction in terms. After all, how can any data sent into the open air be secure? Thanks to the advent of digital cell nets and encryption, only mobsters and terrorists really need to worry about phone tapping any more. And few phone conversations have anything in them that would interest a thief. But what about wireless data sent over Wi-Fi networks? Every time you log on to a public Wi-Fi access point, you are transmitting your login name and password over open airwaves, and often a credit card number as well. And given that public networks offer the opportunity for bad guys to capture mountains of such data, it's right to be worried.

And while individual home networks may not be quite as attractive to wireless hackers, do you really want your neighbor stealing your bandwidth, or passersby snooping around your hard disk? Just over a year ago, surveys revealed that most public and private Wi-Fi networks used no encryption at all, meaning that anyone with a laptop and Wi-Fi card could intercept and read data packets being sent or received by legitimate users.

This could happen even without actually connecting to the wireless router. All that is needed is the ability to "sniff" the airwaves, a rudimentary function offered by dozens of easily downloadable utilities, such as those used by "wardrivers." (Wardrivers are those who wander the streets with Wi-Fi gear looking for networks to join -- most are hobbyists or simple bandwidth seekers, but some are malicious.