The sad thing is that while we all know this (especially if you've spent any time writing Facebook apps), it's our parents generation and our kids that apparently do not. I'm saying that hoping to encourage us all to do a little user-education whenever possible. This link doesn't do much good on HN. Share it with your non-techie friends.

(Side note: I wonder if you could create a Facebook app with the sole purpose of creeping out people with the amount of information they provide?)