Personally, I think smoking is a terrible (stupid) idea. Allow me to explain:
Have you ever noticed, while reading the paper or watching the news, that no one seems to burn alive in house-fires? Most of the time, they die of smoke inhalation.
So... would it make sense to walk into a burning building and breathe in the smoke? Of course not! That would lead to death! A far better solution is to inhale smoke in measured doses, while paying exorbitant prices and medical bills.
An untapped market is drowning. The effect is essentially the same: an unwanted agent enters the lungs and eventually, the person suffocates. My idea would be to sell small vials of water that the person would inhale into their lungs, providing that euphoric feeling of not being able to breath. I can just see the masses lining up now...