Last night (Oct. 23), a few legendary rockers -- like Billie Joe Armstrong, Jesse Malin, Debbie Harry, former Distillers singer Brody Dalle, and Alice Cooper -- performed at the 'Little Kids Rock' benefit concert at New York City's Hammerstein Ballroom. The event helped the organization raise money to bring instruments and music lessons to underprivileged schools.

After the show, Armstrong and Malin showed up at a surprise gig at the East Village bar, 2A, to celebrate rock photographer Bob Gruen's 69th birthday. According to the New York Post, they performed a full set of covers for a very small crowd, from the Clash to Cheap Trick to Blondie. Armstrong is a personal fan of Gruen's work, and also worked with him in 2009 when Gruen took photos of Green Day on top of the GE building.

Cooper was there too, jump starting the night with one of his own tracks, 'I'm Eighteen.' Paul Collins jumped on vocals for 'Hanging On the Telephone,' and although Harry was in attendance for the Blondie cover, she did not perform. You can watch the two shred on the Ramones' 'Sheena Is a Punk Rocker' below:

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