Help! I am looking for the most effective way to quit smoking.

I've been a smoker for 20 years. I am well aware by now of the fact that nicotine addiction is one of the hardest addictions to break. I have tried cold turkey recently, and believe me, by the third day, I really did act like a cold turkey (I have witnesses). I've tried using nicotine gum to suppress the cigarette cravings, I've been brainwashed and slagged off about my smoking habit on countless occasions. I'm not saying the above methods are not effective. There was just one big element missing in the process. The decision to make sure I QUIT FOR GOOD. I wonder, how do you break a habit which has been part of your life for so many years? And how to you break this vicious addiction?