The other day, in the middle of making a left turn from a four-way stop, I realized I’d jumped out ahead of the woman who had the right of way. Aiming to signal an apology, I touched my index finger to my head (“I’m aware I did that”) and then to my heart (“and I feel bad about it.”)
Why did I do that? Is there even the slightest chance this gesture was interpreted correctly by the other driver? More generally, why don’t we have a consensus gestural shorthand for “I’m sorry about the improper traffic maneuver I just executed?” Or do we have one, and I just don’t know it?
Quomodocumque 
In Hawaii, the shaka (http://upload.wikimedia.org/wikipedia/commons/4/42/Gesture_raised_fist_with_thumb_and_pinky_lifted.jpg) is sort of all-purpose this way. “Sorry I did that just now.” “Thanks for letting me in.” “Hey, cool car.” And so on. I think I used to give a little wave of acknowledgment.
I just raise my hand, palm out toward the forehead area and look apologetic. This might be cultural and learned from my Chinese parents. I never can completely tell what I learned out of habit and observation and where it came from.
That’s a great story. My friend Jerrold once thought a guy beeping at him was overreacting to some maneuver he (Jerrold) had just made, so he looked at the other driver with a sad-baby expression on his face and tapped his finger along his cheek, from the corner of his eye downward — i.e., he was calling the other guy a crybaby. The guy jumped out of his car at the next light, ran up to Jerrold’s open window and punched him the face. Jerrold realized, at that moment, that he had it coming…
In Rhode Island, the etiquette is that the person who breaks the rule gives the person with the right of way the finger.
I sometimes do what Christine does (palm raised and out) but the problem is, this reads to me as “I’m alerting you that I’m coming through the intersection, so please don’t jump forward.” In particular, it feels like an implicit assertion that the gesturer does have the right of way, exactly the opposite of what I’m going for. Maybe Christine just has a better “apologetic face” than I do.
Here is one option. Not everybody knows ASL. But I bet more people recognize this gesture than we might guess. And if many people start using it, it could become a trend.
http://www.lifeprint.com/asl101/pages-signs/s/sorry.htm
The problem with hand gestures is that they are culture dependent: a particular gesture in one culture may indicate apology, but in another insult. There can even be differences between generations. MIchelle’s Shaka from a distance might look too close to raised index and pinky fingers. When I was a kid this was an alternate version of the raised middle finger, but I’ll bet that kids today would not recognize it.
In addition to raising my palm, I also bob my head in what I hope is a “mea culpa/I am suffering great shame” kind of way. Off topic – the Orioles are making an impressive run to reach a 100 loss season.
You could hold up a sign that says “SORRY!”