Foo Fighters with Ann and Nancy on Letterman Last Night Will Rock You [VIDEO]

Foo Fighters kicked off a week long residency on the Late Show With David Letterman  Monday night, performing a cover Black Sabbath’s War Pigs with special guest Zac Brown. Click here if you missed it. And how did they top that last night? Heart‘s Ann and Nancy Wilson joined them for ‘Kick It Out’. And it was good...very good! The energy in the audience was vibrating at a super high frequency. Ann and Nancy looked and sounded incredible.