I don't know about them, but with GEICO I get Mechanical Breakdown Insurance for $35 per six months. This will cover any non-warranty repairs with a $250 deductible no matter where it happens. Obviously things like routine servicings and brakes are not included. It must be purchased when the car is new and not allowed to lapse.
Since I tend to keep cars about ten years and 180,000 miles it is definitely worth it for me.