One of the biggest mysteries we'll need to solve for driverless cars is how to assign liability in an accident. Some experts think car manufacturers will start taking on more responsibility, but many insurance companies are still loath to touch the subject because of the various state laws that risk complicating the picture. But at least one insurer seems to sense an opportunity where others fear to tread. In what appears to be an unprecedented move, a British insurance company has begun offering a special policy designed for autonomous and partly automated vehicles. In theory, you could use this on your Google driverless car or your Tesla that's equipped with autopilot.