You don't say?

I'll never forget the first time I went to Sweden, in the late 70's, and noticed another quirky habit they had, which was to inhale sharply as they listened to your conversation.  It was simply meant to signify that they were politely listening to what you were saying, and to signify mild agreement.   To an English speaker, it sounded like you had said something a bit scandalous, enough to startle them. You half expected them to say, "You have now insulted the king, dirty American, and shall forthwith be expelled to Norway!"

Now in Umeå, and probably all points north, there is another hissing sound that they make that simply means "yes."  Makes sense to the Swedes, who are famous for saying things in few words, if they can.  Here, there isn't even a word!  What an amusing language!

Via Tai Wiki Widbee.