Far more rare, however, is a privacy concern involving Facebook's own founder.

Just a couple of weeks ago, Facebook CEO Mark Zuckerberg made headlines when his personal Facebook fan page . Now, Zuck says someone is using his own social network to stalk him -- in a literal and rather unsettling sense.

Facebook that Zuckerberg recently filed a stalking-related restraining order against a man in California. Court records indicate that man is a 31-year-old named Pradeep Manukonda.

According to , Manukonda repeatedly attempted to contact Zuckerberg, both via Facebook and in person -- and reached out to his girlfriend and sister, too. Manukonda is accused of going to Facebook's offices and even Zuckerberg's home to try to see the high-profile tech exec. Some sources say he attempted to reach Zuckerberg in a single day.