How many friends do you have on the most popular social networking site Facebook? Some of us intentionally adds friends or accept almost all who wanted to be friends. But do you know that it can inflict possible harm for us? Con artists are lurking in the shadows of your Facebook, Twitter, Linkedin and eHarmony accounts, according to the North American Securities Administrators Association, the oldest international investor protection association. Crooks have always gravitated to so-called "affinity" frauds, which target the members of a set group such as members of a particular church, alumni association or country club. That's because victims let down their guard when they're introduced through a friend, even if that introduction is second-hand. (Think: "I was referred to you by Father Robert." Or "Sandra suggested that I give you a call.") In fact, scammers purposefully infiltrate tight-knit groups, figuring that common hobbies, li