I've had that conversation a few times as well. Just never at a stop light.
So did you put your electrons where your mouth was and leave him breathing "clean air"?Hehe. I had my first one last week. The guy rolled down his window and waved at me.. First I thought the he wanted directions, but he wanted to know how I like my Volt. Told him I was amazed by it and if I would have know this much before, I would have purchased one way earlier! Then he asked, is it low on power (he prob meant torque) and I told him "It has more torque than my top of the line mazda 3 that I had before... (he was driving a mazda 3 also .. ) made him smile and then light turned green.