Waving "Thank you" while driving

[Larrabee]

A 'rule' I had to learn when driving in the UK was that flashing headlights means, 'I'm letting you through'. That caused some confusion for one poor London driver. Sorry London driver!

Flashing the lights means 'I'm letting you through' but it also means 'thanks for letting me in' if its after dark and a wave wouldn't be seen. 

Not acknowledging that somebody has let you in is considered the height of rudeness here, and if you do find yourself accidentally in the wrong lane or blocking a junction then the embarrassed 'sorry' wave to the people you've inconvenienced will generally get you forgiven.

[Dindrane]

Letting someone into traffic, facilitating smooth merging, or allowing lane changes aren't always or necessarily "kindnesses" - they are things we do to keep traffic flowing with minimal problems; yielding to other drivers even when not strictly "required" is one of the ways to do that. If someone DOES do something that is a kindness, I will always acknowledge them with a wave (not so much a thank you as an acknowledgement). However, if someone has to inconvenience other drivers to offer me what they think is a kindness, I actually get annoyed. An example would be holding up the traffic behind them to insist that I make my turn out of a parking lot, when in reality, I'm supposed to wait until traffic is clear before turning.

This is where I stand.

Personally, I rarely wave, in large part because I don't often merge/change lanes in such a way that I need (or am causing) the drivers around me to behave differently.  If they don't have to slow down or otherwise react to what I'm doing, then they aren't "letting" me in and I don't need to do anything extra.

The other reason I sometimes choose not to wave is because changing lanes is an operation that sometimes requires both hands on the wheel, at least for me.  If I can't safely drive one-handed, then I'm not going to.

[Ruelz]

I wave.  I also do a sarcastic thank you wave wave when they do somehting annoying as opposed to obscene gestures.

Me too.  The wave is a nice way to keep friendly and acknowledge our fellow people out on the road. 

I get quite miffed when someone doesn't wave, esp. when I do make an effort to let them in (when I clearly don't 'have' to)...do they think it was their superior driving skills that gets them ahead?

But I don't nec. wave in a clear 'take turns and merge' situation...although the number of people that won't merge is rather appalling...or, when you clearly signal a lane change and the car coming up will deliberately speed up to prevent you from changing lanes...*argh*

[Wonderflonium]

I always wave when someone does something nice, and I've been known to say "thank you" out loud without thinking. I get irritated when other people don't acknowledge me.

[agentsmith]

Formative years spent in rural-ish Texas.  I wave for a kindness and the opps/sorry wave.  In TX, the hand up off the steering wheel greeting wave at oncoming traffic is pretty much required outside of town.  Here in NC, only in my neighborhood.

[Cricket]

I wave, too, but I don't see other drivers do it very much these days when I'm in the city. I live in rural Queensland, Australia, and there's not much call for letting someone in - we only have one lane either way 

We do use the index finger off the steering wheel to acknowledge someone we know in and around town.

Flashing headlights at oncoming traffic means one of 2 things (in Australia, at least)
1) To warn oncoming traffic that the police are up ahead (usually with a speed camera) - this is frowned upon by the police.,
2) To warn oncoming traffic of a serious hazard up ahead.

[AlwaysQuizzical]

I'm in the U.S., and we flash our headlights in my area for the same two reasons as you! Yeah, the cops aren't wild about forewarning, but it isn't illegal (here).

[Cricket]

Not illegal here, because there are valid reasons for flashing your headlights. Another reason that I couldn't think of yesterday (and it's probably the most important one) is to flash your headlights at an oncoming driver who has neglected to turn of their high-beam. This is the safe way of saying, "Hey, dude, your lights are shining in my eyes and I can't see where I'm going!"

[Yvaine]

Not illegal here, because there are valid reasons for flashing your headlights. Another reason that I couldn't think of yesterday (and it's probably the most important one) is to flash your headlights at an oncoming driver who has neglected to turn of their high-beam. This is the safe way of saying, "Hey, dude, your lights are shining in my eyes and I can't see where I'm going!"

That's the way it's usually used around here--it means either "turn off your brights" or "your lights are off."

[Redsoil]

I do like the "finger flick" one does in country Australia.  Even our sign language is truncated!

[Kitty Hawk]

Here in Germany it is common to wave or acknowledge someone who does you a courtesy while driving.  For example, our neighborhood is full of traffic islands (to keep the speed down), so if two cars meet, one will wait.  That deserves a thank you.