At 10:35 HRS Saturday Morning Millwood and Yorktown FD's were dispatched to a rollover MVA with entrapment on the Taconic NB at the District line. On arrival the vehicle was found on its side and the single occupant had been removed from the vehicle by bystanders through the partially dislodged windshield. Confirming the location in Millwood's District with no extrication necessary and a single patient,Yorktown FD went back in service with Millwood FD's thanks. As the patient was still in close proximity to the vehicle, the vehicle was stabilized with cribbing and traffic was controlled. Upon closer examination, Millwood FF's realized how fortunate the patient was as the guardrail had penetrated the grill area, traveled through the engine compartment, pierced the firewall, and pushed through the lower dash stopping just below the steering wheel inches from the occupant. The patient was collared and boarded by Millwood FF's and Yorktown EMS - then transported ALS to WCMC by Ossining EMS.