DRIVING ALONG INTERSTATE 495 IN THE BOSTON AREA IT WAS RAINING PRETTY HARD.  I WAS TRAVELLING IN THE HIGH SPEED LANE WHEN I NOTICED SOMEONE AHEAD OF ME COMPLETELY STOPPED IN THE SAME HIGH SPEED LANE. I WAS ABLE TO SEE THE CAR IN TIME TO QUICKLY PULL OVER INTO THE BREAKDOWN LANE!  I LOOKED OVER TO THE CAR AND THERE WAS A WOMAN  INSIDE JUST SITTING STILL.  I WAITED FOR TRAFFIC TO CLEAR SO I COULD CROSS THE FOUR LANE HIGHWAY. WHEN I GOT TO THE CAR, THE WOMAN WAS CRYING AND NEAR SHOCK FROM FEAR. I WAS ABLE TO GET HER OUT OF THE CAR AND CALM HER DOWN.  AFTER ABOUT TEN MINUTES SHE THANKED ME AND THEN SHE SAID TO ME   " OH MY - YOUR CAR IS MOVING". THAT'S RIGHT.  I HAD A STANDARD TRANSMISSION AND IT HAD SLIPPED INTO GEAR AND WAS MOVING AWAY ALL BY ITSELF. THE CAR HEADED INTO THE FIRST LANE AND CONTINUED INTO THE SECOND LANE AND THEN THE THIRD UNTIL IT HAD COMPLETELY CROSSED THE HIGHWAY.  OK THAT WAS CLOSE BECAUSE THE ONCOMING TRAFFIC WAS NICE ENOUGH TO AVOID HITTING MY CAR. THEN THE UNTHINKABLE HAPPENED. ONCE THE CAR CROSSED THE FOUR LANE HIGHWAY IT TURNED AND CROSSED THE HIGHWAY AGAIN! THIS TIME THE TRAFFIC STARTED BEEPING AT MY CAR LIKE THERE WAS A PERSON IN IT NOT DRIVING TOO WELL. WHAT WAS I TO DO? I COULDN'T TELL THE TRAFFIC THAT I WAS STANDING OUTSIDE MY CAR.  WELL IT MADE IT ACROSS AGAIN,  HIT THE GUARDRAIL AND STOPPED. I TURNED BACK TO THE WOMAN I'D BEEN HELPING AND SAID OK - BACK TO YOUR PROBLEM! THE TWO OF US PUSHED HER CAR OFF THE ROAD AND I STAYED WITH HER UNTIL HELP ARRIVED.  AS FOR MY CAR - IT WAITED FOR ME UP AGAINST THE GUARDRAIL. MY ONLY CONCERN WAS THE SAFETY OF THE POOR WOMAN WHO HAD BEEN TOTALLY SCARED WHILE STUCK IN THE HIGH SPEED LANE!