You expect X from a band, then suddenly they come along with something that makes you go WOW.. where the hell did that come from?

One that really stands out to me, Beastie Boys, 14th Street Break (http://www.youtube.com/watch?v=e3TSkvj9_7E).

Bad recording, but all the others have been pulled.

I have been shocked many times by bands live. The first time I saw SRV live, before any of his records, I thought I was watching a blues act, then he does a Hendrix set.
Son Seals did "Miss You" (didn't really care for it)
Echo and the Bunnymen did "Roadhouse Blues" and "Midnight Hour"
Hey I gotta run to get over to your house before it gets too late.

Lol.. Run!!!!..

Chuck Brown.....the Godfather of "Go-Go".....doing a CD of old standards with the late Eva Cassidy.

Priceless...................

Steve

I know that.. Chuck Brown is part of the establishment around these parts.. you gotta love him!!!

Beth by Kiss. Made me put away my makeup. Rofl! No, really, I never looked at them the same way after that. Shocked me into realizing how much they sucked.
Jeff Beck - Nadia. he did it when he came 'round with the BB King Jazz tour. Haunting.
Jimmy Page - White Summer. Outrider Tour.

When Radiohead came out with OK Computer, "Paranoid Android" really blew my mind, there were guitar sounds in there I had never heard before ever. I thought this band was really going in an innovative direction. Of course they did go in a new direction, but not in quite the mind-melting way I thought they would.

When i was a little kid, I was crazy about the Beatles and had begun buying singles with my chore money and was given a few albums by extended family on birthdays and Christmas. I had somehow ended up with the earliest stuff (this was the early seventies, so all the Beatles stuff, obviously, was available. Maybe it says something about the conventional tastes of my family). The older brother of a friend of mine had a copy of Revolver, something I had seen in the stores. The guy warned me I wouldn't like it. When he put it on, I couldn't believe my ears. Songs like "Love You To" and "Tomorrow Never Knows" might as well have been written by Martians. Nothing like the Beatles I knew. But I thought it was wonderful and strange. Pretty different than the beat-invasion stuff I was used to.

I remember shuffling through records at what was then the best record store in town in '91. I knew the people who worked there quite well and they just received a copy of Nirvana's Nevermind. When "Smells Like Teen Spirit" came over the speakers, excitement was just flying off the walls. People were shocked. I remember thinking, that's it then, they are going to be huge. No need for me to finish that story.

Then there is the clattering, lurching noise of "Underground," the opener on Tom Waits' Swordfishtrombones. Talk about a departure, from late-night piano bar singer to side-show carnival barker. But in a wonderful way.