I've gotten too many messages from colleagues that have the subject line "Do We Read The Same Books" and it encourages you to sign up for a social software called Shelfari. The "bacn" from this program was sent to a listserv, and it annoyed people on the list. The problem is that the Shelfari uses the "find a friend" feature to spam your friends without permission. So, don't install Shelfari or you will be apologizing to your friends.
One would think that Shelfari would learn from Quechup's mistakes.