Brainiac: Science Abuse, a British show somewhat similar to MythBusters, investigated the danger of using a mobile phone in a petrol station by filling a caravan with petrol vapor and a mobile phone and calling it. They then turned it up to eleven by adding a lot more mobile phones and calling them simultaneously. Then somewhat subverted the trope by blowing up the caravan - by having a man dressed in nylon dance in a bucket then touch the end of a long wire running to the caravan.
"The Lazarus Experiment": The Doctor uses an organ as a sonic weapon. When it fails to produce the required results, he says to himself "Need to turn this up to eleven", before using the screwdriver to do exactly that (the readout changes from 100 to 110).
The Eleventh Doctor does this quite a lot. It's in the name.
Good Eats did a straight-up reference to This is Spın̈al Tap in one episode where Alton's assistant Paul makes a toaster that goes up to eleven. When another character asks why he didn't just make ten higher, he starts freaking out until Alton puts him in time out.
The technical challenges on The Great British Bake Off normally condense part of the recipe down to one step (for example, "Make a chocolate ganache") to see if the contestants can do a standard cooking task from memory. In the finale for series 7, this was taken to the logical extreme by doing it to the entire recipe.
The House season 6 episode "Epic Fail" includes House joking about this to Wilson:
Wilson: Doesn't this seem a little bit obsessive? House: Should've been here when I was butchering the ox. What do you expect? I'm an addict. I turn everything up to eleven.
In "TB or not TB", House and Foreman have a bet going on whether a test will gain any results. As soon as it looks like House is losing, he turns the dial up to 11, gets expected results, as well as $20.
iCarly: In "iOMG", Gibby and Carly put Spencer into a box for their project to see how he reacts to different stimuli, one of them being stink gas.
Gibby: Hey Carly, check this out! I turned the stink gas up to eleven! Spencer:slides down the side of the box
The pilot for The Incredible Hulk (1977) involves David Banner deliberately exposing himself to gamma radiation after having deduced it creates a capacity for inhuman strength in moments of crisis. He uses an existing medical device to deliver the radiation and (on the second go, after nothing happened the first time) turns the exposure dial to the maximum setting. Unfortunately, he doesn't know that the device was modified so that the maximum setting was in fact much higher than the markings indicated.
Modern Kamen Rider series love to use the Swiss Army Hero trope, with the last new form gained being the Super Mode - and often those very Super Modes get even stronger variations in tie-in movies:
Kamen Rider Fourze: One of the movies lets Fourze gain the powers of his ally Meteor, in a form called Meteor Fusion States. The next movie lets him copy two allies with Meteor Nadeshiko Fusion States.
Kamen Rider Wizard: Like Kuuga, Wizard gained a Dragon Mid-Season Upgrade to his original "Styles" (Flame to Flame Dragon, Water to Water Dragon, etc.) - and, like Kuuga, there came the moment in a tie-in movie when his Infinity Style Super Mode got boosted up to eleven as Infinity Dragon Style. And then another movie pushed it even further into Gold Infinity Dragon.
Tom Servo jokes a bit during the Mystery Science Theater 3000 episode in which they watch Devil Fish, when the monster attacks the ship with its tentacles.
MythBusters has a policy of "Duplicate the myth, then replicate the results." They first test a myth under the claimed circumstances, then ramp up the test to see just what it would take to produce the results the myth claims. And then sometimes they'll take it up to ridiculous levels after that, just for the sake of making a really big explosion. Said explosion will ALWAYS demand MORE DAKKA!!!!!!!
One episode had them taking many of their previous myths and just pushing it up to insane levels. For example, the myth about the exhaust of a jet engine flipping a car. They'd confirmed the story in the original episode (if only through archive footage; because of insurance concerns they'd been unable to properly do the test that time). In the later episode, they tried the taxi again (and got it to flip), but then they decided to see if it could flip a bus. (It could.)
The cement company accidentally overfilled that truck, and the entire load had set. Tory had unsuccessfully tried to loosen it using a jackhammer, and it had pissed him off. The truck deserved everything it got. At the time it was the biggest explosion ever done on the show (now it's only 3rd or 4th biggest but still one of the coolest). There was very little left of that truck afterwards.
The build team did this when they busted the myth that a sheet of paper can be folded in half only 7 times. It culminated in producing and folding a huge sheet of paper (with the same ratio of width to length as a standard sheet of printer paper) in alternating directions to achieve a maximum number of folds... of eleven.
Another person got it up to twelve using a different pattern of folding and a differently shaped piece of paper — i.e., folding in a single direction using a very long strip of paper.
The Hindenburg episode had them using scale models of the Hindenburg to test the myth that it was the chemicals on the skin of the airship rather than the hydrogen that destroyed it. It turned out to be a "contributing factor". Then - just for the hell of it - they took the last scale model, pumped it with hydrogen, and coated it with seventeen pounds of pure thermite. It burned. Oh yeah, did it burn.
Another episode has them trying to cause two tractor-trailer rigs to fuse together in a head-on collision, with a compact car being crushed between them and lost in the wreckage. They crashed the trucks into the car at highway speeds, but there was no fusion, and the car was still partially there. Next, they built a rocket-propelled sled with the proper mass and crashed it into the car at 700 miles per hour. Still no fusion, though it did successfully make the car vanish, bend a piece of 1-inch-thick steel plate in half, and throw a multi-thousand-pound block of concrete about thirty feet. They eventually resorted to explosive welding. (The car wasn't just destroyed. It was vaporized.)
The rocket sled had an encore performance when the team was attempting to split a car in half with the blade of a snowplow. Previous attempts had fallen short when the plow blade encountered the bulk of the target car's engine block. With a makeshift plow blade bolted to the top of the rocket sled, however... well, that was no longer a problem.
Psych: Used word-for-word by Lassie when asking Shawn and Gus to be over-the-top crazy in order to drive away Lassie's new partner. They are very excited to comply.
In the episode "By Any Other Name" of Star Trek: The Original Series, the Enterprise is modified, and goes to Warp 11. Such a speed was near inconceivable beforehand.
In Star Trek: The Next Generation, "Force of Nature", LaForge is found to be engaged in friendly competition with Commander Donald Kaplan of the USS Intrepid over their respective ships' power conversion levels. Kaplan does manage to one-up LaForge by 0.1% shortly before a speed limit of Warp 5 is imposed across all Federation starships.
This is actually makes sense, considering that we learn in "Relics" that Scotty frequently padded his figures so he would look good when he managed to coax more power from the engines. One can infer that because he wrote the book on warp theory that's treated as gospel by modern Starfleet engineers, most Federation ships are actually underpowered as a result.
The concept of "anti-time" took Rocks Fall, Everyone Dies Up To Eleven. In Q's alternate timeline, Picard is accidentally reponsible for an energy field that grows as it travels backwards in time, to the point where 4 billion years ago, it has consumed most of the galaxy and prevented life on Earth from evolving in the first place.
Top Gear has a few examples of this, a recent one coming from episode 12x03 where Jeremy Clarkson presents to the audience a food blender powered by a 6.2-liter Corvette V8. It could blend a brick.
On the last episode of series 13, Hammond is reviewing the Holden VXR8 Bathurst with a supercharged LS2 V8 engine. His exact words: "What this car does is go to 11."
On TV Heaven, Telly Hell, Jimmy Carr refers to Flavour of Love as reality TV "up to eleven".