you'd better smile....

Here's a question of etiquette for you: you're in the car park at work, you're about to leave for home and you find that you get back to your car at exactly the same time as the person in the car right next door to you.  He's fiddling about in the boot, and you open the door of your car.  Your car isn't parked too close to his, but you know how sometimes the door slips open a little wider than you were expecting and it gently dings the side of the car next door?  His car.  Yeah... that.  And he's standing right there.  It's only a gentle ding and there's no harm done, but still....  You quickly pull the door back and look up anxiously.  The guy has clearly heard something and is looking over, you're not sure he quite knows what he heard, but he's looking in your general direction.

What should you do?

I ask, because this happened to me in the car park at work this evening, only I was the guy fiddling around in the boot.  What this guy did was he gave me a slightly sheepish smile.  But what am I supposed to do?  Go ape-shit?  I smiled back, almost reflexively.  We've all done it, after all.  It's just his bad luck that I happened to be standing right there when he did it to my car.  So I smiled at him, silently absolving him and letting him know that it could have happened to anyone.  Marvel at how phlegmatic I am being!  This car is 4 months old!  I am so calm.  I am a zen warrior.

Then I stood there, waited for him to leave - going so far as to pretend to be opening the driver's door to get in - and as soon as he left, I nipped round the other side of my car to have a closer look.  There was nothing to see.  It was just a gentle little ding.  It happens all the time.

On reflection, I'm not sure a sheepish smile was enough penance.  I know I blew it by smiling back, but come on!  Dude!  I was standing RIGHT THERE. 

But what do you do?  What would you do?