Finian's Rainbow

A Broadway musical from 1947, created by Fred Saidy (book), E.Y. Harburg (book and lyrics) and Burton Lane (music). Due to its popularity it was revived several times. It was adapted into a feature-length film in 1968 by Francis Ford Coppola, starring Fred Astaire and Petula Clark.

"Petrified parsley, petrified parsley, petrified parsley..."

—Sharon McLonergan

The story follows Finian McLonergan, an Irish immigrant and his daughter Sharon to Missitucky, USA. He has stolen a magical pot of gold from leprechauns back in Ireland and plans to plant it in the ground near the Fort Knox. Og, a leprechaun in charge of the treasure, follows him, desperately trying to get the gold back. They stop in small community led by a carefree Woody Mahoney, and matters are further complicated by corrupt senator Rawkins, Finian hiding and losing the gold, and the magical properties of the gold itself.

This musical and its 1968 film adaptation provide examples of:

An Aesop / Anvilicious: Racism is not cool, OK? To be fair, it was written in the 1940s and some anvils really do need to be dropped.
Blue Blood: Spoofed:

Finian: Don't you realize, lad, Sharon is from quality stock? Why, her whole family tree for generations back consists of nothin' but ancestors.

Woody: We've been descendin' a long time too.

Finian: Ah, but how long? Sharon's grandparents go back to the dawn of history. Blue-blooded amebas they were, with a dauntless ambition. Up they came through the paleozoic slime -- from ameba to tadpole, from tadpole to daffodil, from daffodil to dromedary, and from dromedary to McLonergan. That's the background Sharon comes from -- so get along with your luggage, lad, you haven't a chance.

Burn the Witch: Almost happens to Sharon and Woody, after Sharon accidentally turns Rawkins black. They are saved Just in Time.
But Now I Must Go: Finian, at the end.
Color Me Black: Sharon tells a racist senator she wishes he were black so he would understand what black people have to go through due to people who think like he does. She happens to be standing where a pot of magical wish-granting gold is buried, so... well, you can guess where this is going.
Cue the Flying Pigs

Woody: I'll raise the money somehow.

Buzz: Money don't grow on trees, you know.

(Money starts falling from the tree they're standing under, thrown by Sharon who sits up there.)

Cut Song: "Necessity" was removed to shorten the movie.
Cute Mute: Susan the Silent. Until the end.
Gospel Revival Number: "On That Great Come-And-Get-It Day"
Dawson Casting: Petula Clark was in her 30s when she payed Sharon.
Double Standard: "When the Idle Poor Become the Idle Rich" discusses this at length.
Everything's Better With Rainbows: The story takes place in the Rainbow Valley.
Doomy Dooms of Doom

Og: Doom and gloom! Dooooooom and gloooooooom!!!

Heel Face Mind Screw: What Og does to Rawkins. The Family-Unfriendly Aesop that often comes with this trope is arguably made somewhat less creepy by the fact that Og is, y'know, a lepre chaun.
Humanity Ensues: Throughout the story, Og is slowly turning into a human due to losing his pot of gold. By the end, he's become completely mortal. And he doesn't care.
In Love With Love: "When I'm Not Near The Girl I Love (I Love The Girl I'm Near)."
Irishman and A Jew: Incorporates elements of Irish folklore (more or less) and features an Irish protagonist; the show was penned by an all-Jewish writing team.
Karmic Transformation: Openly racist senator Rawkins gets turned black. The trope gets a nice twist when he gets to love his new life and is forced to turn back by his own laws.
Large Ham: Og, in the film at least.
Last-Second Word Swap: In "When the Idle Poor Become the Idle Rich":

And when all your neighbours

Are upper class

You won't know your Joneses

From your Astors

When we're in the dough

And off of the nut

You won't know your banker

From your butler

Leprechaun: Og.
List Song: "The Begat."
Love At First Sight / Fourth Date Marriage
Oireland: Supposedly where Finian and Sharon come from.
Mobile Shrubbery: Hilariously performed by Og.
No Communities Were Harmed: Very obviously Missitucky.
No Except Yes: In "When the Idle Poor Become the Idle Rich", Finian explains this pretty clearly.
Pair the Spares: Og and Susan.
Panty Shot: Susan the Silent, a number of times.
Perfectly Cromulent Word: "Something Sort of Grandish" is built on this:

Og: [...]It's so terrifish, magnifish, delish.

To have such an amorish glamorish.

We could be oh, so bride and groomish

Skies could be so bluish blue.

Life could be so love in bloomish,

If my ishes could come true.

Politically-Incorrect Villain
Scenery Porn: The beginning of the film.
Three Wishes: The magical pot of gold can grant them.
Wet Sari Scene: Susan in the "Rain Dance Ballet" scene.