Last night (May 15) at the Acoustic-4-a-Cure IV benefit concert in San Francisco, the Foo Fighters debuted a song titled "The Sky Is a Neighborhood." Performed by frontman Dave Grohl, drummer Taylor Hawkins and keyboardist Rami Jaffee, it marks the first new material since the band released the St. Cecilia EP for a free download in November of 2015.

"I figured on the way up here, I thought, uh, f--- it  -- let's play a new song man," Grohl said to the Fillmore crowd. "We never played this in front of anybody."

There's no telling how the track will sound in its final form, but for this performance it features a middle breakdown followed by Hakwins taking on a portion of the chorus before Grohl rejoins him. The Foos have a series of festival dates and headlining shows scheduled this summer which can be found here.

The Acoustic-4-a-Cure benefit was created by Sammy Hagar and James Hetfield, with a vision was to raise needed funds and awareness for the pediatric cancer research. All of the proceeds from the event go to UCSF Benioff Children's Hospital. This year, Grohl was standing in for Hetfield, who is currently on tour with Metallica. The show also featured performances by Hagar, Steve Vai and Bob Weir among others.

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