I thought this was funny and pretty insightful: an article from a dad on his reading about advice for prison guards, and how he realized it was applicable to parenting. For example, these are seven things never to say to anyone:

1. "Hey you! Come here!"

2. "Calm down!"

3. "I'm not going to tell you again!"

4. "Be more reasonable!"

5. "Because those are the rules!"

6. "What's your problem?"

7. "What do you want me to do about it?"

"If you've ever been a child or have your own, you undoubtedly recognize those as the greatest hits of the pissed-off parent. As the father of three kids under five, I've probably said some variation of each of these phrases dozens, if not hundreds, of times."

http://www.motherjones.com/media/2011/06/parenting-tips-prison-guards