The danger was compounded by an overhead power cable, which broke loose and fell on the roof of the rear car, causing further arcing and a large amount of smoke inside the train.

BBC: Metro train fire

Telling Google engineers that their Google projects destroy cable TV or book publishing by making them obsolete should be much easier, certainly easier than building a driverless car.

WSJ: The Weekend Interview With Sebastian Thrun: What's Next for Silicon Valley?