There is one very well known guaranteed cure for smoking--death. However another one has just been discovered--brain injury:

Scientists studying stroke patients are reporting that an injury to a specific part of the brain, near the ear, can instantly and permanently break a smoking habit, effectively erasing the most stubborn of addictions. People with the injury who stopped smoking found that their bodies, as one man put it, “forgot the urge to smoke.”

This is great news. We may be able to find or create a drug or other means to "flip the switch" and help people from implementing the "universal cure".

I find this very ironic--I always figured you must have had a dysfunctional brain to start smoking in the first place.