I once did that driving. And not on a straight stretch of road, either. I was driving home and thinking about a woman I was seeing who really made me feel good. I negotiated turns, stop signs, maybe even a traffic light or two, when suddenly I noticed there was a strange car in my driveway. I had no recollection of the drive home, couldn't remember any of the drive, and only snapped out of it when something odd happened, a strange car in the driveway. I'd like to think if I had needed to be alert I would have snapped out of it sooner, but who knows?