I've never had it done to me, but then I'm not that stupid as to walk by a bloody great puddle in the road when there's cars coming! I would hope that if I ever am so dense, and I do get a soaking, I'm able to laugh it off with the same intensity that I'm sure the driver of the car will be.
I may or may not have done it a couple of times, and the reactions of the people has been absolutely priceless: The classic open-mouthed cape-wearing pose