Was making my way across 6 lanes of Atlanta morning traffic to get into the HOV lane as I do every morning. After a quick glance in the side view mirror and a look at the display to make sure the next lane was free I began moving over when an incredibly loud alert sounded and the car yanked me back into my lane as another vehicle sped by at a high rate of speed. I never saw him and it would 100% have been an accident and even though he was speeding I'm certain I would have been at fault. The corrective move by the car was very quick and decisive. I was not in AP at the time. I'm impressed.. and thankful.