Temporary Passwords for Using Facebook on Not Your Computer

Want to protect your Facebook password when using a strange computer (i.e. not your private computer)? In a couple weeks the mega social network is introducing what it calls "temporary passwords." 

Here's how it will work: a Facebook user must register their cell phone numbers in their Facebook account. When accessing Facebook from a strange computer the user can text a number from the phone and Facebook sends them a temporary password that is good for 20 minutes.