I don't know about you, but I trust that face.
In reality, "blowing off some steam" and "letting yourself go" is probably one of the worst advice you could ever get from someone that means well. Other than your friend Bill or Robert at english class, thousands of organizations have built real-life therapies for such people with this same concepts; examples would be stress balls and punching bags. But before you start swaying your hand at me in a disapproving and discrediting manner, hear me out.
If a person decides to express their anger and frustration regularly, they may find themselves more angry and frustrated than ever before. The act of taking out your anger by flipping your desk over a loud scream acts as a temporary relief from life's woes and troubles. But who would ever want it to be temporary, right? Why can't we live in the ecstasy of the moment forever? Either consciously or unconsciously, you may find yourself becoming "addicted" to the rush from smacking your boss across his smug face and begin to strive for that same relief you've felt before.
"I got you a gift, it's in the palm of my hand."