There is an article in NYT on this subject: http://bits.blogs.nytimes.com/2013/09/10/beyond-passwords-new-tools-to-identify-humans/?_r=1& http://bits.blogs.nyti

There is an article in NYT on this subject: http://bits.blogs.nytimes.com/2013/09/10/beyond-passwords-new-tools-to-identify-humans/?_r=1& http://bits.blogs.nytimes.com/2013/09/10/beyond-passwords-ne... , although it is mostly about hardware authentication.