One that I found effective is for me to just take the child for a car ride and talk.
Some say it's the vibration from the car, others say it's the time away from any distractions such as TV, Video Games, Computer, iPod, etc ...
Either way, my kids usually calm down and stop misbehaving after our car ride together. Eye to eye contact helps a lot too.
I've included a photo below of one of my sessions, in case you would like to use the technique.
