Social networking safety
When using social networking sites, (i.e. Facebook, MySpace, Twitter, etc.) make sure to set your profile settings to "private" so that people you don't want to have your personal information can't access it. There is a staggering amount of personal information that "we" put on these sites that can easily be used for retaliation.
One cop's fight to keep personal info secret
Equally important is to make sure that your spouse doesn't have any information on his/her profile that identifies that you are in law enforcement and that you are related. I even go so far as to list my marital status as single (to my wife's dislike) so I do not have to worry about a criminal obtaining who I am married to. I have explained to my wife the importance of not identifying what I do on the Internet.
Just as we use NCIC to obtain information on individuals, criminals can use these social networking sites to obtain information on us.