Every once in a while Facebook gives me a list of suggested friend based on the fact that the suggested person and I have a large number of mutual friends. For the most part, I recognize the suggested individual and remember that there was a reason why I did not befriend them in the first place.
However, every once in a while, the site suggest I friend whom I don't recall even seeing once in my life. Sure enough all of my friends know this person. Even worse, is when this person you are sure you never met is tagged in a picture with you.
This makes me feel guilty.