When you think about a driverless car future, perhaps your mind goes to being driven around, watching movies from the backseat and drinking martinis. For over a decade, perfect driverless cars have seemed only a few years away. But in reality, they were nowhere close. Now, driverless cars are finally being rolled out in some cities. But (like humans) they're crashing and causing chaos. So are driverless cars finally here? Or is teaching a car to drive simply too difficult?