My grandfather used to tell this joke:
I was riding in the car with a friend of mine once and we came to a green light and he stopped. The light turned red and he went through it. The next light was green and he stopped. When it turned red he went through it. I was getting nervous so I asked my friend if he ever had any driving lessons and he said “Sure! My brother taught me how to drive.” So I said “Well surely you know that green means ‘go’ and red means ‘stop’?” to which he replied “of course I do but my brother might be on that other street!”
To put a little cheese on the top my grandfather would add:
My friend’s name was ‘Red’ and in response I blurted out “Right on! Red!” so he turned right at the red light and from that day forth it’s been legal to make righthand turns at red lights.