"It just turned red" to me and a host of other crosswalk users with a lit " walk" sign. In Cambridge MA, behind the alewife T station, major hub for trains, bikes and 2 roads. Rindge ave makes a T out to fresh pond ave. Like I said, lots of traffic. 3 walkers on the far side, me, one other biker and a woman with a double stroller on my side. We start to walk. The light has been red for at least 5 seconds, we are all in the crosswalk. I see him flying up, I'm off bike and just push it forward. He screeches to a stop around the corner, like 30 ft. Words ensue. I'm jawing, moma bear with the 2 cubs ( kids) is crazy mad. She had to pull her stroller back to not get clipped. She is now at full yell/ swearing/ starts hitting this punks mustang. He rolls up the window and backs down quickly. I truly thought she was going to drag this guy out of his car for a beat down. She looked like she might. And could. I told her to snap a pic of the plate and make a report, I would witness if needed. Seem to deescalate things ok then.