This is an interesting story about a study of the economics of privacy in social networking:
Personally, social networking sites concern me less from a privacy standpoint than institutions such as the government and financial institutions. I follow the rule that sites can’t disclose what they don’t know. I simply won’t voluntarily give any site personal information that I want to be kept private. If they ask for it, I just make stuff up. Unfortunately that is usually not an option when dealing with financial or government institutions.
I guess that makes me a privacy fundamentalist.