When you forget your Gmail password, and have two factor authentication (2FA) enabled, Google will SMS or call you with a six to eight digit code. You enter the code (Google calls this 2-step verification) and gain access to your account.
2FA - News, Features, and Slideshows
The Australian Taxation Office holds the voiceprint of one in seven Australians, according to figures released to Computerworld.
In an ideal world, people would not need a password to log in to Facebook as they would use a hardware token instead, according to Facebook United States engineer Gregg Stefancik.