Isaac Hayes, "Walk on By" (1969)
Isaac Hayes' 12-minute version of Burt Bacharach's "Walk on By" from his legendary 1969 LP Hot Buttered Soul is a bold choice for a sample. Not only is the original a classic, but the record has already been sampled by a hip-hop who's who: Tupac, Biggie and, perhaps most memorably, the Wu-Tang Clan, who rapped over the record unmolested, even giving Hayes a feature credit. Yet producers Danny Boy Styles, Ben Billions, Boots, Dixie and Beyoncé transform the record. On an album focused on a relationship's fall, it's not a surprising sample — but it's used on "6 Inch," an anthem of affirmation for working women. It's as if the song reminds its empowered protagonists of the heartbreak lurking in the background.