It's never been more important to add two-factor authentication to your online accounts. Two-factor adds another layer of protection in case your password is stolen or hacked, by relying on a physical thing you own. Normally this is done with a cell phone, where you get an SMS or phone call. But maybe you're tired of hauling out your phone every time you log in to your Gmail or GitHub account? That's where physical USB tokens can make your life way easier. These work seamlessly on Chrome or Opera web-browsers, with no drivers or special plugins. Just press...