9. "I Will Follow"
"It's coming from a very dark place," Bono said of the opening track – and crowning moment – on U2's debut, noting that it was inspired by "real anger and an enormous sense of yearning." Written about the love between a son and his mother (Bono's died when he was a teen), it gave stomping U.K. post-punk a heraldic urgency. "I remember picking up Edge's guitar and playing the two-stringed chord ... to show the others the aggression I wanted," Bono recalled. "The percussion in the drop was a bicycle spinning, wheels upside down and played like a harp with a kitchen fork." "I Will Follow" quickly became their live trump card; the Edge recalled a Boston gig where they played it three times, as set opener, closer and encore, to a rapturous crowd. "We left the stage feeling incredible."