I agree with Mc Grath's comment about smoke from cigarettes just left to burn. I once moved an ashtray with a smouldering cigarette away from me to a place downwind of the smoker. He went spare - "I don't want all that smoke going into my eyes and face" he shouted. When I suggested that he might extinguish it (after all he'd only had about two puffs) his reaction made me find another table (I had been there first) for my own safety.

On a lighter note, I recently heard a northerner say "When I were a lad, we didn't have any of this passive smoking - yer 'ad to buy yer own fags".