On reflection, it wasn't downtown exactly, but a shopping district that had a three-lane street running through the middle of it with traffic lights that changed the direction of flow in the center lane depending on time of day.
Which is relevant to issues of "traffic shaping" in a network engineering sense. Adaptive trunking, anyone?
Just be glad it wasn't Comcast running that 3rd lane. Otherwise they'd take all the blue cars (pick a color), make you call home saying you weren't coming, and then they'd dump the car (and probably you) down a bottomless pit.