Tribute is a song by the 2-man rock band Tenacious D; the song, first put to wax in 2002, details the story of two travelers confronted by a demon (played, in the video, by Dave Grohl of the Foo Fighters, said demon demanding they play "the best song in the world" for him, else he will eat their souls (putting aside the quixotic problem of how such an insubstantial thing as a "soul" could be masticated). So, the song tells, the duo dynamically spontaneously burst out with "the best {or "greatest"} song in the world," and so condemn the demon back from whence it came.

They then point out (in the song itself) that the song they are then singing is not the greatest song in the world, but is instead "just a tribute" to that song -- which they could not remember. This brings to mind the interesting ontological argument question of whether it is even possible to "know" something that is the greatest manifestation of a given abstraction, such knowledge being necessary to precipitate the actualisation of that manifestation.

The scene is replicated with a vital modification in the Tenacious D movie, The Pick of Destiny, but there the characters, engaged in a "rock-off" with the Devil, are not required to perform "the best song in the world" but merely one that rocks harder than the Devil's. Interestingly, they fail at this because the Devil's song is just soooo much more rockin' (with the Devil calling them lame and preparing to take KG as a sex slave as his prize) but evade the consequences of losing when the Devil's magic is reflected back at him off JB's guitar. The movie's reconceptualisation of the confrontation lifts from the players the burden of having to put out there a song which could match Tribute's promise of being "the best song in the world."