Related link: http://news.bbc.co.uk/1/hi/technology/3639679.stm
I ran across this story in The Week that was on the top of my reading stack today.
Researchers asked if people on the streets of London if they would reveal their login passwords in exchange for confectionary.
I did not find what they actually offered, or even if they offered an actual cholocate bar. I do not know about anyone else, but I would hold out for something better than Cadbury.
What you take in exchange for your password?