‘O Brother, Where Art Thou?’ (2000)

Perhaps the last soundtrack that was a phenomenon that dwarfed the film it came from (in this case, the Coen brothers‘ little-seen Depression-era comedy). Carefully curated by T Bone Burnett, this soundtrack of roots-music and bluegrass gems sold eight million copies, won the Album of the Year Grammy, and sparked a massive roots revival that continues to this day.