20 years ago today, on July 18, 1993, Rage Against the Machine protested against the Parents Music Resource Center at Lollapalooza III by standing naked onstage with duct tape covering their mouths and the letters PMRC on their chests. The band used up their performance time without playing any songs. The only sound emitted was audio feedback from Tim and Tom’s guitars. (x)

“The brilliant reason for that,” Brad Wilk explains, “was Zack blew his voice out that day. Couldn’t sing. It was either cancel or do a half-ass show. We were in Philadelphia - the birthplace of American independence - and thought, ‘We need to take advantage of this, is everybody cool with being naked?’ 'Yeah, yeah, yeah.’"  (x)