Welcome to rap’s Album Era — there were others before it, but this one busted the market wide open and made Queens’ original hip-hop ultrastars the first rap group to [INSERT ANY NOTEWORTHY SALES/ACCOLADE MILESTONE HERE]. There’s a subversive charge to the rock crossovers — both direct (Aerosmith collabo “Walk This Way”) and sample-based (Knack-jack “It’s Tricky”) — but the fundamental lyrical power of “Peter Piper” and “My Adidas” opened a new world to the longhairs that we’re better off living in.