The Humming Chorus of Puccini's Madame Butterfly could be considered three of the most beautiful wordless minutes in all of opera (particularly when you hear it in context). I just found out, from a glance at the score . . .
that the viola d'amore part (which is hardly ever performed with an actual viola d'amore) is supposed to be played from the stage. That really changes everything. The chorus of humming sopranos and tenors is off stage, Butterfly, Suzuki, and baby Dolore are in silhouette behind the screen of their Japanese house waiting motionlessly for Pinkerton to return, and the only movement you see (in Puccini's inner eye and score) is a viola d'amore player, with a scroll that reminds us that love is blind.
There is a visual echo of a viola d'amore scroll a few measures from the end of the second act when Butterfly blindfolds her son.
[No spoilers here for those who have not yet experienced the opera.]