If you’re concerned about the privacy and security of your wireless Internet connection, I’d recommend you listen to episode #89 of the Security Now podcast. In this episode, Steve Gibson highlights a new attack on the flawed WEP protocol that is often used to secure Wi-Fi connections.
I abandoned WEP for the successor, Wi-Fi Protected Access (WPA) protocol, awhile ago. Nowadays, it is easy to switch to WPA as support for the protocol is very common. Off the top of my head, you’ll find support in Windows XP, Windows Vista, Mac OS X, and on devices like the Xbox 360.
Of course, WPA is only as strong the password. If you need need, Steve Gibson provides a random password generator here.
If you interested in learning more about Wi-Fi (in)security, check out episodes 10, 11, and 14 of the Security Now podcast.