I WAS DRIVING MY TOYOTA PRIUS UP MY LONG AND FAIRLY STEEP DRIVEWAY OVER ABOUT AN INCH OF SNOW WHEN THE POWER SUDDENLY KICKED OUT BECAUSE OF "THE TRAC" SYSTEM AND I SLID BACKWARDS INTO A TREE. IT HAPPENED A SECOND TIME WITH JUST A SMALL DUSTING OF SNOW. I GUIDED IT INTO THE MOUNTAIN BUT DAMAGED THE EXHAUST SYSTEM RUNNING OVER A ROCK. I NEVER HAD A PROBLEM WITH MY PREVIOUS CAR WHICH WAS A SATURN SEDAN. THE TOYOTA DEALER SAID IT WAS A SAFETY FEATURE WHERE THE ENGINE CUTS OUT IF THERE IS ANY WHEEL SPINNING AND TO GET SNOW TIRES WHICH I DID (WITH STUDS). STILL I RARELY GO OUT IN THE SNOW ANYMORE. IT STILL SLIPS ON OCCASION EVEN WITH THE STUDS. IT WOULD BE ESPECIALLY DANGEROUS IF ANOTHER CAR WAS BEHIND ME. LUCKILY THE TREE STOPPED ME OR I WOULD HAVE GONE INTO A RAVINE. OTHER OWNERS HAVE COMPLAINED TO CONSUMER AFFAIRS BUT TOYOTA HAS NOT ACKNOWLEDGED THIS SAFETY PROBLEM. *JB