I do not smoke, but have in the past. I'll try and explain my reasons here, in case anyone might be interested.
The first thing I'd like to mention here is that, no matter what you say, smoking is goddamn cool. A lot of senselessly dangerous things are, so just live with it. If I see someone sat with a glass of wine and a cigarette, I think 'cool'. You probably do, to (at least if you've ever spent time in Europe). This is not really relevant, but I just wanted to get it off my (still functioning!) chest.
See, I actually took up smoking a short while ago (definitely old enough to 'know better') and then quit almost a year afterwards - and I did it mainly as an experiment. An experiment, that is, to ease the curiosity of never having known what it is like to be genuinely addicted to something. Properly "I need this" addicted. I mean, I thought I liked chocolate, but I'd never found myself counting the minutes until I grabbed my next mars bar.
But yes, it was interesting in many ways. First of all, nicotine is definitely great stuff - everything smokers tell you about being more alert, awake, on-the ball and in control is absolutely true. If I were to try and describe the effect, I would say that it makes it much easier to be happy. It doesn't make you happy, or alter your state of mind in any really noticeable way, but you'll just find yourself being more contented in what you are doing. You'll be more ready to be pleased with yourself, if you will. And that's nice.
However, I did stop. Smoking is, really, quite naff. Everything anti-smokers tell you about it stinking, making you feel dreadful in between every spark-up, and effecting your general health is also absolutely true. But the strange thing is, I didn't actually care at the time. I only decided to stop because I realised that it had become a habit. I had started to do it less for the positives and more to placate the negatives. It had become irrational, and I didn't like the thought of that.
So yes, I quit. And it was hard. Really hard, actually. I'd probably still be at it now if it wasn't for a Scandinavian friend of mine introducing me to Swedish 'Snus' - a moist ground oral tobacco (debatably) reckoned to be nigh-on carcinogen free. It seems to have none of the drawbacks of smoking, yet all of the benefits (apart from the 'cool' factor - in fact, a wad of sticky brown mud in your top lip is the opposite of cool). It also leaves your hands free for more important things; I mean, try using emacs with a lit ciggy in your hand! I'd say everyone should use the stuff, but it's hard to get a hold of in the EU (senseless blanket ban) and, well, you can imagine how inelegant it is. Certainly helped to wean me off the fags.
All in all, I'd say that it was worth doing. I can now very happily play devil's advocate to any smoking-related rant and have learned to disassociate the practice from any notion of a person's awareness, intelligence or background. Smoking is cool, smoking is pleasurable and, and this is far from unimportant, it is something to do, other than working, studying or idling. And, although this post turned into what seems like a rather off-topic essay (and has perhaps added to the shame I feel at not keeping a blog), I'd like to think that, while the opinions expressed here may not be particularly enlightened (or even interesting), they should, at least, be well researched.
... I think I might need to spark one up. (NO!)