Noticed something new today when I was trying to login to my windows live account. There is a new option which says : Not your computer? Get a single-use code to sign in with. This appears as a link right below the sign in button.
What is Single Use Code ?
If you are on a public computer or on a network which you do not trust instead of giving a password you can sign in using a code which is sent to your phone number. This number is not just any number but should be a number already associated with your account already in your account settings.
This option is only available for Argentina, United States, United Kingdom, Turnkey, Spain, Mexico, Netherlands, Japan, Italy, Germany, Italy, Germany, France, Colombia, China, Canada, Brazil and Australia.