I go to a lot of sidewalk protests at which protesters hold signs for passing motorists to see. Some motorists honk their horns in support.
My favorite part of these protests is when pedestrians and bicyclists, who don't have horns to honk, enthusiastically SAY the word "honk", over and over. "Honk!" they say. "Honk! Honk! Honk! HONK!"
Sometimes, passersby who didn't previously know each other form an impromptu chorus, all saying "Honk!" at the same time. It's great!