tentacles 

Just skip at 0:40 and start to listen. Hilarious.
This is a musical based on H.P. Lovecraft's Cthulhu mythos, but even if you haven't read his books this is funny.
Made by H.P. Lovecraft Historical Society.
Lyrics are copied from Stacey Greenstein's comment and I made some additional tweaks.
A Shoggoth on the roof
Sounds crazy - no, certifiably insane!
But here in our little village of Arkham, Massachusetts, you might say every one of us has a Shoggoth on the roof
And I'm not speaking of metaphorically!
It's not easy having a... malevolent shapeless monster like that, hanging over your head, but there it is!
Arkham is the home of many strange things
A big monster like that on such a pointy roof
You may ask: How does it stay up there, if it's so difficult?
That, I can tell you in one word: Tentacles!
Tentacles, tentacles! Tentacles!
Tentacles, tentacles! Tentacles!
Here in Arkham, tentacles get into everything eventually Changeless, legend-haunted Arkham, where the clustering gamble-roofs sway and sag over attics, where witches hid from the king's men in the dark olden days of the province
Well, the king is gone, but the witches are still here... and the cultists, and the monsters, and regular folks just trying not to notice We try not to think about the scariest one of all; the gigantic half-dragon, half-octopus half humanoid Great Old One himself, Cthulhu, waiting to return from his city beneath the sea!
Who day and night must slumber in R'lyeh, wave his tentacles having nasty dreams? And who has the might as master of R'lyeh, to drive humanity insane?
Cthulhu, Cthulhu! Tentacles!
Cthulhu, Cthulhu! Tentacles!
Who must bow in mirrors(?), scrape and slave all day, to raise R'lyeh, Cthulhu's way?
Who must live in ignorance until the day, they find they've read too many nasty books?
The cultists, the cultists! Tentacles!
The cultists, the cultists! Tentacles!
At nine I started growing gills and swimming in the sea
And soon I'll know the wonder of the sunken city
The Deep Ones, The Deep Ones! Tentacles!
The Deep Ones, The Deep Ones! Tentacles!
Who's always last to know, who fills the air with cries?
Whose sanity is blasted, and then who usually dies?
The victims! The victims! Tentacles!
The victims! The victims! Tentacles!
(Chorus)
We have the shoe factory, and the brick works, and the wonderful insane asylum we're all mighty proud of, but the heart of the town is it's Miskatonik University. It may not be the biggest school in New England, but there's no finer place in the world to study medieval metaphysics.
It's my honour to be its head librarian. You'll see many folks from the university as you walk through Arkham's streets, and in our small community, we've always had some special types as well...
For instance, Herbert West, the mad scientist.
"Those small-minded doctors have needlessly and irrationally delayed my supremely great work! The reanimation of dead tissue is within my grasp!"
"Herbert, your perverse experiments are the vagary of a demented maniac and cannot be allowed to continue. Your request for the use of human cadavres is completely denied!"
"I warn you, doctor Halsey, you will regret this decision".
And Randolph Carter, the writer with the weird dreams, who keeps showing up everywhere.
"I repeat to you, gentlemen, that your inquisition is fruitless. Question me forever, if you want - I do not know what has become of Harley Warren!"
"Mr. Carter, there's a telephone call for you".
And Obed Marsh, the cursed old man from nearby Innsmouth.
"What are ye lookin' at? What, ye think I'm ugly? Is that it?! I'll be showin' ye ugly!".
...
Then there are others in Arkham. Some of them live here, some of them just visit. The head of a local cult, some kind of horrible monster. I do not even want to know what that is. We normal folk just look the other way and try not to lose our minds. And among ourselves, we get along just fine.
Well, of course there are some who think that the magical Elder Sign is shaped like a star, and some who think it's shaped more like a tree... but that's all settled now. Now, we just try to-
"It's shaped like a star with a little flame inside it!"
"It's shaped like a tree - it's got branches coming off it!"
"I'm telling you, it's a star!"
"Use the star one and you'll be fighting off the Old Ones with your bare hands! It's a tree!"
Star! Tree! Star! Tree! Star! Tree! Star! Tree!
Tentacles. Like I said, you cannot live in Arkham without coping with the shoggoth on the roof.