If you're traveling for the holidays, be careful when you use wi-fi hotspots in public places. "Few things expose your [computer] to greater security risks than latching onto a public Wi-Fi service," USATODAY reports. "Computer criminals can 'sniff' the traffic in a cafe, or set up a fake hot spot that you might innocently log into. When that happens, watch out: Everything you type goes directly to the host computer, known as an 'evil twin'." The "twin is ready to grab passwords, financial info, etc. Some retailers with wireless service are now advertising secure connectivity, which really helps. If you log on and see "https" instead of "http," your connecting is also probably secure. USATODAY has a sidebar with other tips.