I'll probably need to wait for this prompt to come around a few times—there are so many great picks just off the top of my head. But top of my list must be the sinister-sounding performance of Half Day Closing from Portishead's Roseland NYC Live album, building and swirling to that extraordinary eldritch howl. The audience response at the end says it all. They knew they were party to something special that night.
In the days, the golden days
When everybody knew what they wanted
It ain't here today
Dreams and belief have gone
Time, life itself goes on
