1. Pink Floyd, 'The Dark Side of the Moon' (1973)
Easily the peak of prog rock's commercial success — and often cited as trailing only Michael Jackson's Thriller in total global album sales — Pink Floyd's lean concept album has soundtracked countless planetarium light shows and just as many critical unpackings. From its sync-up with The Wizard of Oz (press play after the lion's third roar) to the Flaming Lips and friends' track-for-track covers project to Krusty the Clown's lost Dark Side of the Moonpie to the endless hawking of the prism-and-rainbow logo, the album has endured as a pop culture touchstone since its release. Sonically, it covers classic rock ("Money"), soul ("The Great Gig in the Sky"), glam symphonia ("Brain Damage"), chiming clocks ("Time") and analog synthesizers (pretty much all of it). Lyrically, Roger Waters was universal yet personal, peeling back the human condition's paper-thin skin. For all its Alan Parsons-led studio innovations, the underlying accessibility of Dark Side is its greatest strength. After all, they're only ordinary men. R.F.