In the age of on-demand, digital-streaming music, who has the superpowers necessary to transform a motley collection of AM radio hits from the 1970s into the No. 1 album in the U.S.?

The answer, as summer movie fans know, is Disney's almighty Marvel Entertainment Group, maker and marketer of billion-dollar-grossing superhero films, including this summer's "Guardians of the Galaxy."

Last week, the movie's soundtrack became the first in history to reach No. 1 on the Billboard Top 200 without including a single original tune. Everything — from the first track, Blue Swede's "Hooked on a Feeling" to the 12th, Marvin Gaye and Tami Terrell dueting on "Ain't No Mountain High Enough" — is at least three decades old and easily available as a free download (legal or otherwise) or digital stream.