Did this once. Was on my way home late at night and was so horny. I was rubbing myself through my dress pants and got to a point where I had to go for it. I pulled it out and went for it while heading down the hwy. it had been a couple days since I had cum so when it happened it was pretty intense! There was cum everywhere. My pants, shirt, steering wheel, dashboard, gearshift, window on the car door. It was pretty crazy trying to clean it up in the dark with two small napkins. Next day had to go back and clean up what I missed in the dark!