Big No/Web Original

This Photoshop comic parodying A&W's commercials shows Ryan throwing Allen a birthday party. Allen invokes this trope when Ryan announces he's giving away free Mama Burgers.
Necro Critic did this when he found out there was more to Ehrgeiz than just the terrible fighting game. This one lasted past his 30-second long end screen and continued even after stopping for air.
The end of the season 3 finale of AH Dot Com the Series: after it's revealed that they inadvertently overwrote the location of the Planet of the Nymphomaniacs in the ship's memory banks, the entire crew lets out a Big No so loud it literally echoes off distant galaxies and is heard in other dimensions.
A popular internet meme is RAEG, where a template comic strip is drawn on, with the ending of a grotesque face shouting "FFFFUUUU--" in situations like a no smoking sign, being caught watching porn, etc.
The Leet World's Chet usually greets the death of his drinking buddy Player with a cry of "Player, NOOOOO!" However, since the show is set inside a Video Game, dead characters are usually back in action next round. A notable exception is when Player is injured by Ahmad's grenade, as this took place outside the challenge levels where death is permanent. Lampshaded in the episode "Thunderhead" when Player breaks cover runs into the line of fire. Westheimer shouts "Player, No!" and Chet comments that it sounds better when he says it.
The Angry Video Game Nerd: In the "Christmas Carol" episode: "NOOOOOOO! NO! NO! NO!", when the Ghost of Christmas Future shows him his tombstone, in the style of Castlevania II: Simon's Quest.
In the Zero Punctuation review of Spore, Yahtzee delivers a deadpan Big No. Twice. Both times in his inimitably snarky manner.

"So can his new game Spore possibly live up to that legacy? In short, no. In long, noooooooooooooo..."(total length: 17 seconds)"...ooo.
So I guess what I'm asking is, 'Can brightly coloured monstrosities really compare to Batman?' Short answer, Nooooooooo..." (interrupted by closing music)

Julian and Tarquin from The Chin Review are really, really attached to their cheese and wine.
In the Whateley Universe, Phase does this once, upon learning something horrific about herself during powers testing.
At the end of the Five Best and Worst Sonic Games countdown, Stuttering Craig does one, when he finds he can't turn off the music to Sonic R.
The Nostalgia Chick does this on being exposed to the Christmas Shoes song in her "Top 10 Disturbing and Inescapable Christmas Songs" special. The Nostalgia Critic also shouts this frequently. A notable one is when he finally finds out that The Star Wars Holiday Special does, in fact, exist... and that he has to review it.

Nostalgia Critic: No... it's not true... it's impossible!!!
Darth Vader: Search your feelings, you know it to be true!
Nostalgia Critic: NOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOO!!!!!!!!!!!

- She also does it when Nella dies by "bridge drop" during the Kirk VS Picard review.
- The Nostalgia Critic gives a series of these in his Drop Dead Fred review. Some of them are comparatively small "no"s, but he makes up for it with quantity.
- The Nostalgia Critic has "I HAVE A NEGATIVE RESPONSE TO THIS SCENARIO!!! I HAVE A NEGATIVE RESPONSE TO THIS SCENARIO!!!" This while making fun of Tombstone's Big No. However he actually lists this trope as one of his favorite clichés.
- Rob (dressed as Emperor Palpatine) tells Doug (dressed as Darth Vader) that he must review the 1999 animated movie The Legend of the Titanic. Guess the result.
In The Battery's Down Courtney has one of these when Jake says he's quitting musical theatre.
Raocow did this seemingly unintentionally. Made extra hilarious by how loud, deep, and scary it is compared to his regular voice.
Also from a Let's Player, Chuggaaconroy's occasional Epic No. To be fair, it isn't a long, drawn out "NOOOOOOOO" as much as a deep, harsh "NO!", which in context is a rejection, not the cry of despair seen in movies/other media. Chuggaaconroy parodies himself in this video at about 11:46. "And there's Luigi's Epic NOSE!"
Let's Plays of I Wanna Be the Guy will often have this. Even the creator of the game himself has been pushed this far. Here's a much more dramatic one
- As does Let's Play Sonic 2006.

NO! NOOOOOO!

The Yogscast Let's Play of Minecraft resulted in this in the Shadow of Israphel arc, upon finding out that the airship crashed into and completely destroy the two players' Yogcave, complete with an epic zoom out.
5-Second Films has a fourth wall-straining example (also counting as a case of Skyward Scream) in "Boarding School". Lampshaded in the description:

"Unfortunately for Junior, he's getting shipped to St. Understated, Thoughtful Conclusions Academy. Life's gonna be rough."

- Also a quieter-than-usual (but angry) example as an opinion on planking.
The Annoying Orange: Orange at the end of More Annoying Orange and Cheese at the end of A Cheesy Episode.
Spoony reacts this way in the "Party Mania" review first to suffer an eternity of a party in Canada and the second time when he will lose his 'wiener'.
- He mocks the use of one in Tekken: Blood Vengeance, arguing that they hadn't really reached the Noooooo! stage of a relationship given their three minutes of screentime.
NOOOOOOOOOOOOOO!!!!!
Two in Water Human, both very dramatic and ending abruptly. First, the Water-Human cries out over David Hasselhoff's corpse, before realizing that it's weird to angst so much over a guy he knew for less than a minute. Later on Water-Human and a prison warden cry over the Large Beetle, who claims to have a heart attack, but then reveals he was just kidding.
Chad Vader does this when he finds out that his girlfriend Libby has been deported, only for the Marshmallow Bandito to harass him.

Chad: You picked the wrong day to mess with me, nerd! (beats him up)

Marik Plays Bloodlines:

Marik: I'll just work on my tan. Wait. I'm a vampire. I no longer have a tan. NOOOOOOOO!

The end of the "Sloppy Roethlisberger" episode of EPICMEALTIME has Harley accidentally breaking and spilling an entire bottle of Jack Daniels, with this being the appropriate response from someone in the background.
A couple of times throughout Nakar's Let's Play Ultima series, but most memorably right at the end of Ultima VI.

Beh Lem: "To be saying nooooooooooooo in slow motion!"
Death Cannon: *BOOM*

Lenore the Cute Little Dead Girl: After Lenore dies, Ragamuffin shouts one while he begs to Lenore's corpse to not leave him.
- The Ladybug from Last Dance of Ladybug also gives one after she was injured by a kid.
Twice in Two Best Friends Play. One was Pat's response to the thought of paying for all of Vampire Rain, and the other is when Matt found out they were going to play Shaq Fu.
Gronkh often shows this reaction, for example on various occasions when being killed in Minecraft, (most often by a creeper, for example here).
Shiny Objects Videos: In "Fishsticks", being the World of Ham that it is, a Big No was all but inevitable.
In the Eddsworld episode "Zanta Claws II", Tom has only recently gotten a present of reality eyes. Zanta however is about to kill the real Santa. Tom takes the shot while letting off one of these. The shot hits his eyes, reflects off them and hits a chandelier, crushing Zanta at the cost of his eyes.

Tom: I hate Christmas...

In the Team Four Star Let's Play of the Left 4 Dead 2 custom campaign "Detour Ahead." Just after barely surviving most of the finale, Gan gets two in:

Lani: OH MY GOD A TANK!
Gan: NOOOOOOOOOOOOOOOO! NOOOOOOOOOOOOO!

- Said tank promptly killed Kaiser and incapped the rest of the team within 7 seconds of Lani's warning.
Cloud8745 from YouTube provided a pretty epic one during a challenge run of Kirby's Dream Land