Blindsided by a Song

Looks like this week's theme is going to be music.  I kept on thinking about how I was 'blindsided" by Coldplay's "Viva La Vida" song and became immediately obsessed with it.  It made me try to recall those songs from my musical history that also came out of nowhere.  There have been plenth of songs that I connected with on first listen, but I guess for the purposes of this classification, I'm trying to remember songs that upon hearing for the first time made me stop in my tracks and say "What the heck was THAT??"  Also, I had to not know who it was upon first hearing.

So far, the list is made up of only one other song:  "Let's Go Crazy" by Prince.  I remember clearly the first time I heard this song.  I had no idea it was Prince and I remember spending the next hour or so trying to get through to the radio station to find out who it was.  I was stunned to discover it was Prince.  At that point, I was not a Prince fan at all.  His most recent song at the time was "When Doves Cry", and I kinda hated that song.  So I was almost disappointed to discover it was Prince.  But if it was Prince that sang that amazing song, then so be it.  I had my parents take me to a record store (the old Bookworm's Apple) and in short order, that tape was the only thing I listened to for the next few weeks.  Ah, memories...

I'm sure there are others that came out of nowhere, but I can't think of them right now. 

Are there any songs that absolutely blindsided you and went from unknown to your all-time top ten from the very first time you heard it?