Post Secret is a website that displays people's secrets on 4"x6" cards. Anyone can submit a secret as long as it is something that you have never told anyone and it fits on one side of a postcard (or at least mailable material). New secrets are posted to the site every Sunday and then replaced the following week.
There is something really fascinating about reading other people's secrets. They all seem so genuine. I really like the idea of telling a secret anonymously. It's like writing a message in a bottle and sending it out to sea... only we all get to read it. Previous secrets have been turned into books. Check them out on Amazon.