The motion trackers in Aliens. Not only does the rising tone of the detection chime become outright terrifying, especially in the tense build-up to the "Last Stand" scene, but even the soft "paf" of the tracker when it'snotdetecting anything causes fear because you justknowwhat it's leading to. Tip: if you want to wake up quick, program this sound to be your alarm clock's sound the night after watching Aliens. Additionally the screeches and hisses of the aliens themselves are quite terrifying.
There's also the infamous siren. It's made all the more unnerving because it isn't a traditional-sounding siren, instead being a rhythmic, high-pitched noise that sounds like someone screaming.
The sound of Jafar in Aladdinlaughing. Especially his laugh at the end of Prince Ali the reprise]].
Altitude: After the characters have been flying through the storm for a while, and it doesn't seem to end, and their altimeter says they should be in the stratosphere... all they can hear on the radio is this horrible screaming sound.
Children of Men"You know that high-pitched ringing sound you hear? That eeeeeeeeee? That's the sound of the ear cells dying, like their swan song. Once it's gone you'll never hear that frequency again. Enjoy it while it lasts."
 and "I'm singin' in the rain, just singin' in the rain..."
The metallic droning screech given off when the spaceship starts up.
There is a high-pitched noise as if one's ears are ringing whenever the fluid's effects on Wikus become apparent but the exact extent of it isn't known yet. It's first heard when he's sprayed in the face with it, then when he throws up, when he experiences a nosebleed, when his fingernails come off, and when he trows up again at home.
For example, in one scene, Christine is alone in her house at night when she starts hearing strange noises, including screeching sounds, creaking, and thumps from above. The lights then go out, some hanging pots and pans suddenly clang together, and then light enters the house showing the shadow of a demonic figure. An invisible force then blasts her backwards into a counter, leaving her with a bloody lip.
In the movie Dragon: The Bruce Lee Story the presence of the samurai armor clad demon is accompanied by convincingly realistic off-screen shrieks of agony and fear. Considering where this demon had just supposedly come from, this might be the most literal example of this trope yet.
Oh god, Eraserhead. Throughout the whole movie, there are a lot of jump scares involving noise, like the artificial chickens, the demon baby thing getting sick, and the sound of a baby crying. For about fifteen minutes straight. The last ten minutes or so are nothing but high pitched static and the sounds of a baby screaming.
"Liberate.... me..." Free me. Except that's all they could hear over the horrible distortion and grisly screams. It's later found out to be "liberate tuteme ex infernis", or "save yourself from hell." And the sounds were the crew and ship tearing each other - and themselves - apart in a horrible orgy of violence and madness. One of the more literal interpretations of the trope in question.
Indio's watch chime in For a Few Dollars More. Every time it plays, you know someone is going to die horribly.
Irreversible contains a nearly-inaudible, low-frequency noise intended to make viewers uncomfortable. It is apparently there to cause sensitive viewers to leave the theater before things get really bad.
It: The inhuman noise Pennywise makes whenever he gets those fangs.
The Ju On films, and their remakes, The Grudge films. The croaking sound made by Kayako (her death rattle) will haunt your nightmares for weeks. Same with Toshio's piercing cat meow.
The earth-shaking noise (and the water rippling usually coupled with it) whenever the T. rex is walking in Jurassic Park. You are so screwed now...
The raptors tapping their claws in the kitchen chase scene. The whistling-chirping sounds the raptors make to communicate are also very unsettling.
In Kiss Me Deadly there's the hideous, dissonant sounds when the mysterious suitcase is opened. It's supposed to be a nuclear explosion gearing up, but it sounds more like something out of Hell itself.
Parodied in Kung Fu Panda - the jar that contains a thousand souls makes a deliberately ominous "oooOOOooo" every time someone even touches its pieces.
One of the things Jackson had not merely right, but perfect.
Also, that tapping noise that happens right after Pippin drops a stone in the well in the same chapter.
The Nazgűl screeching. It's so horrible that in universe it causes people to just fall where they are and scream while covering their ears. Created by recording and blending numerous sounds, including co-producer Fran Walsh screaming. She had a throat infection at the time. Fans joked that Jackson got her to make that sound by telling her he was going to do a film of The Silmarillion next.
The Loved Ones tells the story of a deranged girl who kidnaps a boy and tortures him. One of the first things she does is inject his vocal cords with bleach to silence him. When she eventually begins her Cold-Blooded Torture his resulting screams are this trope times a thousand.
Mama': Anything that comes out of Mama's mouth is this.
Man of Steel gives us General Zod's terraforming devices and ships, which emit this horrible droning noise that even makes the ground shake.
That scream in Men Who Hate Women. It will haunt you in your dreams, as well as return later in the series.
The squawk Bing's violin makes when the shadows swallow him in MirrorMask.
Monty Python and the Holy Grail for such a silly, entertaining movie, the eerie howls that can occasionally be heard in the background (such as when Galahad's limping towards Castle Anthrax) are genuinely disturbing. Can you imagine being in the rain, wounded, locked outside a castle, listening to those mournful howls come closer and closer?
Subverted in My Cousin Vinny. Seeking a quiet place to rest, Vinny and Lisa have borrowed a cabin in the forest. The silence is broken by a horrific screech, Vinny jumps up WHAT THE FUCK IS THAT and starts shooting at random into the trees. The culprit, a screech owl that could fit in the palm of your hand, merely blinks and turns around on its branch.
Night of the Demon features a high-pitched chittering sound that precedes the appearance of said demon, or at least threatens imminent arrival.
Night of the Living Dead did this a couple of times - the zombie feast was understated and otherworldly; the death of Helen Cooper was a series of highly distorted screams; even the last bit of music during the photo montage of the posse disposing of the bodies...
In Day of the Dead one character's head is slowly pulled off by a horde of zombies. As he screams, his vocal cords are pulled taut and finally snap...
Oblivion (2013): The drones', well, electronic droning, consisting of dissonant warbles which almost sound like an attempt to form words. In practice, they resemble someone hitting a digital keyboard at random notes; in effect, it's an extremely unsettling "voice."
One Missed Call has the ringtones. Here is the American version, and here is the Japanese version. Both qualify, although YMMV on which fits this trope more.
Also in The Orphanage, the knock on the wall game that the protagonist plays with one of the ghosts. She has to face the wall to knock on the wall and say a little rhyme and each time she turns around, the ghost is a little bit closer.
And Tomás's rasping breathing.
Paranormal Activity has a a trigger sound of the presence arriving to do its business, which sounds like some sort of rumbling, which was probably meant to be the audio track being distorted by the presence.
The footsteps of the demon 'walking' down the hall during the preliminary hauntings turn out to mirror the shuffling noises we hear just before the 'pop out and scare you' moment in the last scene.
Katie talking about her paranormal experiences that include hearing long scratching sounds and the calling of her name.
The titular Piranha announce themselves with a watery echoing gargling/burbling chitter. It's creepy to young impressionable ears, but when you're older it sounds like a flock of scuba-diving turkeys.
Pontypool: Sydney Briar is alive. Sydney Briar is alive. Sydney Briar is alive.
The opening narration is rather unsettling as well. Hell, anything Mazzy says could be registered here...
How about it playing back the soldiers' conversation?
From Predators, when they realize the Mexican dude is dead, but the Predator keeps playing his voice. Then it starts playing some variations of that same voice. It sounded like a five-second chorus of disturbingly calm souls begging for help FROM HELL.
Wet sneakers in the first Resident Evil movie. Think it's a survivor? Dead wrong, it's a zombie with a broken foot.
The squeaking, creaking sounds the Wheelers make as they roll around in Return to Oz, and especially their laughs.
In the American remake of The Ring, the cursed videotape contains an odd, rising-and-falling-in-pitch squeaking sound that loops constantly. It's scary because it quickly becomes associated with Samara's attacks, but the repetition - it's the exact same sound every time- is creepy on its own.
In the original Japanese movie, the videotape contains a grating, high-pitched squeaking sound which is heard multiple times throughout the movie. It is creepy. Also, during the ending, a single, high-pitched squeak is heard repeatedly when Sadako is coming for Ryuji... and it only rises in pitch as she gets closer to emerging from the TV.
In the same movie, the barely-audible speech of the "Towel-Headed Man" from the video (used twice in the first film and then used once towards the end of Ring 2) will haunt you.
There's also a short, incredibly high-pitched whine (for those of you watching the Tape: it's the sound of the finger pushing down into the nail) that tends to come up every once in a while.
You'll also never listen to forest sounds, like insects and birds, the same way. (These precede the infamous Well Scene.)
Buffalo Bill clicking his night vision lenses into place and turning them on.
Simon's voice from Session 9. But especially the way he says that last line, over the final shot drawing away from the abandoned asylum, just before the credits roll and shortly after watching everybody die except Gordon, who went Ax-Crazy and killed them all. "And where do you live, Simon?" "I live...in the weak...and the wounded, Doc."
Clicking noises and baby monitors. A winning combination in Signs.
Silent Hill: The air raid siren that sounds just before bad things happen.
Everything about Jabba's palace; the screams of possibly sentient droids being tormented by a sociopath, Oola's screams of terror as she's devoured by the Rancor, those damned gates opening up for R-2 and 3PO, even Jabba's distant and derisive laughter can be terrifying with the right timing. All of these are a testament to Ben Burt's sound design, and one damned good screamer.
The Thing (1982): The blood test scene where MacReady casually puts a heated wire to a tray of Palmer's blood and the blood explodes with a hideous screeching sound. It should be hilarious but it's horrifying.
The Thing is overall one of the greatest masters of this trope in cinema. The scene where the lights go out in Fuchs' room (it only attacks in the dark) and as he walks to the door with a candle, a shadow darts by with a...sound so alien, there are no words in the English language to describe it.
The Bennings-Thing's scream. It still disturbs many fans of the movie. And in some fanfics, it causes a reaction of horror in the individual cells of any non-Thing life form.
The combinations of sounds from the Jed/Kennel Thing. Especially that insect droning.
In Titanic, the ship herself can be heard groaning louder and louder as the film progresses. The passengers are all too aware of what these sounds mean, especially when the top levels of the ship start going under water. The groaning directly before the grand staircase dome breaks and the ship splits in half are downright ominous and haunting.
Many real-life survivors claimed that despite the darkness, they could literally hear the Titanic and her remaining 1500 passengers slowly dying in the night. And then the silence came...
Toy Story 3 has one. When night falls on Sunnyside Daycare, a Cymbal-Banging Monkey sits in the second-floor security office, watching all the screens. If a toy tries to escape, he turns on the center's P.A. system and screeches into it while banging his cymbals.
In the second Tremors movie, about 48 minutes into the movie the Graboid screams, and it is one of the most chilling sounds you'll ever hear.
The Troll Hunter has an absolutely nerve wrecking build-up to the first troll being revealed. First, flashing lights in the distance accompanied by the sound of trees being uprooted. Then, the audible sound of some very heavy footsteps. Wait.. is that growling?
Remember me, Eddie? When I killed your brother, I talked just... like... THIS!
The Wizard of Gore has a prolonged screeching sound frequently used in scenes where the heroes realized something is horribly not right with the scene. Contrasts heavily with the cheery jazz music as Montag gleefully rips gobbets of flesh out of his victims.