I am a relatively recent non-smoker who is old enough to remember legally smoking in flight. The teensy little ashtray in the armrest, the ashes all over my clothes, burn marks in the upholstery!
The US departure terminal at YVR has a smoking lounge sponsored by Benson and Hedges. Within months of the terminal opening this was a stinking pit, even with the heavy duty exhaust/ventilation (I can testify, I was there puffing away!). By the time I quit I could hardly imagine smoking indoors anywhere anymore.
I suggest Nicorettes for the really long flights. You can buy them without a prescription in Canada now.