Hindsight

There is an idea for a series of brief films I had some time ago, at a time when I was driving regularly, that is so simple and easy to pull off that I cannot (and, indeed, do not) believe it has never been used as station idents, ads, or simply for youtube.  I'd prefer, though, to describe what I pictured before...let's say polluting my vision, by seeing how others have pulled it off.

Just this: a shot from the perspective of the front seat of a car, of the car behind in the rearview mirror.  A little slice of life is playing out back there: two people arguing, or headbanging, or talking animatedly, or wearing a Tudor costume and a Gorilla costume and staring out opposite windows.  There's no sound from that car, but only the diagetic sound in the perspective car, which would be used (subtly, please!) to overlay thematically the action in the mirror.  It could also be possible to see out of the windshield of the perspective car, depending on depth of focus and how it's framed, so that could open up more possibilities.  The duration of each--only the length of a stoplight.