Fragmentary, funny, and fascinating, Fugazi’s 1999 Instrument Soundtrack accompanied a pseudo-documentary of the same name, directed by the band’s long-time ally Jem Cohen. It’s without a doubt the least conventional Fugazi album. But it’s a favorite of Fugazi’s Ian MacKaye, because it’s the sound of four pals messing around—a cool snapshot of the band’s working process. Most of Instrument Soundtrack is the sound of songs coming together link by link and yard by yard, as each track is assembled, jammed out, and pulled apart. “Lusty Scripps” finds Guy Picciotto swapping out his trademark trembly guitar, and swapping in his clarinet; “I’m So Tired” is a genuine piano ballad; and the original demo for “Guildford Fall” will remind old fans that this End Hits track started out as a muscular instrumental. Instrument Soundtrack is likely best experienced after a full digestion of the band’s catalog—as well as a viewing of the movie itself. Yet, oddly enough, it’s also the record that includes one of the band’s most popular songs: “I’m So Tired”—essentially a solo showcase for MacKaye—blew up on streaming services after a ukulele cover version went viral. Its success demonstrates how easily the internet can strip music of its context—while at the same time finding new uses for old ideas.