I think a lot about the McGurk effect. The effect is a perceptual phenomenon in which a person "hears" what they see when audio & visual do not match up.
I feel this is the foundation of concrete poetry. Something I've been playing with recently as part of my poem-a-day project.
day 467 - falling
day 469 - cacophony
day 472 - lady dawn (after sappho as translated by anne carson)