I really hate to admit this but when I was in college I got shitfaced at a kegger and was (ahem...sorry MADD)
driving home when suddenly I heaved all over the dashboard of my car. In my drunken stupor, I simply pulled into a self-serve carwash, popped a couple of quarters into the machine, opened the front doors and hosed my dashboard off.
Needless to say, the next morning was not a good one.