Whether they have any extant function or not, they have lost their former function and in that sense they do fit the definition of vestigiality. Vestigial structures are often called vestigial organs, although many of them are not actually organs.
There are quite a few birds famous for doing ritualized mating dances, so I would only list 5: The Red Capped Manakin, The Black-footed albatross, The Western and Clark's grebe, The Superb bird of Paradise, & The Victoria's riflebird.
Below is some of the most popular birds used as a symbol in feng shui applications. Butterfly. Butterfly symbolizes love, romance, happiness, immortality and rebirth. Image of butterflies is often used as a temporary cure by feng shui practitioners for any area of your life that needs change or transformation.