Mysterious Stranger

Sudden hand cramp while driving!  Oh no!  I pull up to the light and take off my glove, shaking my hand.  And then out of the corner of my eye I see movement - the guy in the next car is also shaking his hand and staring at me.  Awkwardly, I wave and look away.

Then he rolls his window down.

Great.  Can't be rude to the random stranger.  I crack my window as well.

Stranger:  I know what you're doing!  Your hand is cold!

Me: ...yeah!

Him:  Our heater broke this morning!

Me: ...I'm sorry to hear it!

Him:  Yeah, it's a cold day for it!  I hope they fix it by the time I get home!

Me:  Yeah, man, me too!  *light turns green*  Stay warm!  Happy new year!

This was followed with me driving very carefully so as to not end up stopped at a light with him again.