http://eater.com/archives/2010/09/07/restaurant-will-not-tolerate-your-screaming-children.php
I think this is one of the smartest things I've ever seen. As a parent, I know how annoying it is to have a child scream through dinner, even if she's mine. I certainly don't want to go for dinner and have to hear someone else's kid scream.
Edit: I understand kids have bad days, BUT the parents shouldn't act like its ok. Because its not, not all. Its disrespectful to everyone around them.