Use security software
Your laptop should have the same anti-virus, anti-spyware, and firewall protection that your home computer does. The firewall is particularly important when on a public network. Its entire purpose is to keep snoops out of your system. You can find excellent free security software, including firewalls, at my Security Center.

Protect your mobile gadgets with apps such as Lookout Mobile Security. They’ll warn you when you're on an unsecured Wi-Fi network, detect security flaws in your other apps and prevent you from clicking on fraudulent links.

Look over your shoulder
Not all dangers in the digital world are high-tech. While you're watching the world go by in a busy airport lounge, a snoop could be literally looking over your shoulder with the hope that you might reveal a username, password or credit card number.

It's called shoulder surfing, and it still works.

Preventing this is equally low-tech and effective. Just exercise a little healthy paranoia!