Do you know what the Green Wave is? Most cities have them.
It's the speed at which you can get through all the lights on a particular route on green. Typically the Green Wave speed will be slightly above or below the actual speed limit, but if everyone did that speed, the street would flow like the bowels of someone who's had a dodgy curry. Instead of course, people zoom along, changing lanes, desperate to be first at the next red light, more like an intestinal blockage.
But why does the Green Wave work? Simple - if you drive too fast, you'll get to the next set of lights before they go green and you'll be stuck waiting on red. Drive too slow and you miss the next green cycle completely, arriving too late and once again sitting looking frustrated at the red light.
The speed limit on 7th East near where I live in America is 45mph. The Green Wave speed is an unpublished 48mph. In the Netherlands where I used to live, there were published Green Wave speeds on some roads.
So go green - find the right speed and, traffic allowing, you'll see much fewer red lights.