I'm not sure that electronic cigarettes do use chemicals to extract the nicotine as such - the nicotine comes in liquid form in a cartridge, and is simply vaporised when you draw on the cigarette.
That said, I've tried them and didn't get on with them. The reason being that because you're allowed to smoke them anywhere, the temptation is greater. I found myself going out for a normal cigarette and then taking a drag of my e-cig within five minutes sometimes, just because I could.
Anyway, I'm someone who smokes and drinks pretty much every day, plus I'm a regular marijuana user, and I have tried a variety of other drugs in my life as well. So my philosophy is very much along the lines of, so long as it's not hurting anyone else, it's my body and I can do what I like to it.
And to the comments regarding the effect that drugs can (do?) have on the IQ, as previously pointed out it very much depends on the person. Of course if you take them to excess then they will have an adverse effect, but it's the same as everything - all in moderation. You could argue that if you eat too much of any particular "healthy" food it would damage your body in some way, so that's no different really.
Like I say I've taken many different substances in my time and will continue to do so. I'm still a reasonably eloquent and intelligent human being, with a decent enough job and a happy life, so why the hell not!