Two mobile incidents:
First one: driving along a narrow country road, I see a car coming the other way, as we both approach a passing place. As I get there a bit before him, I pull into the side of the road. As he passes, he takes his right hand off the steering wheel to wave a 'thank you'. Very courteous, but I'd have preferred it if his left hand had been on the steering wheel at that moment, rather than holding his mobile to his left ear. "Look, no hands!"
Second one: an open convertible being driven by woman overtakes me coming up to traffic lights. Given that she was going to have to stop for the lights, and I was pulling alongside her, I could virtually read the text she was composing with her left hand. I can't remember exactly what I said in her left ear, but she rapidly stopped texting and looked duly guilty.
Re the smoking in cars thing, I wish it were made illegal while driving: all the actions smokers do - removing cigarette from packet, lighting fag, removing hand from wheel for each drag, looking down into lap/bushing off fag ash from lap - are just as liable to lead to accidents as talking on a mobile.