4. There's One Person You Cannot "Block" On Facebook... And That's Mark Zuckerberg
As if Mark Zuckerberg didn't have a good enough life as it was what with him being one of the richest people on the planet and the fact his Facebook wall can be accessed by simply typing "/4" - he also cannot suffer the ignominy of being "blocked" on the social network. If Zuckerberg has added you as a friend or you have accepted his request, you cannot then block the Facebook CEO - even if he was to say something disparaging about you.