I slept while I drove today... I woke myself up by accidentally pressing my horn. I was on a highway and I got really frightened by the possibilities that could have happened while sleeping. Thank god I woke up.
That's what trains do to me (even the thought of a train makes me yawn ). I've just arrived at my place after a three-hour ride and feel well rested
I've never fallen asleep while driving though, but I don't drive that much either.
Last week we were driving home on the highway and my mum and I were asleep. My dad fell asleep with the car on cruise going 110 km/hr and the car drifted into the ditch between the divided highway at that speed. We miraculously got through without a scratch and no damage even to the car!