Grand Theft Auto: Vice City features the "Love Juice", the favorite drink of the band Love Fist: 3 fizz bombs, 1 part boomshine, 3 parts trumpet, and 1 liter of petrol. Boomshine itself could be considered a Gargle Blaster. It's potent enough to intoxicate someone on the fumes alone, and if put too close to an open flame, will detonate like a weapons-grade explosive. One of its ingredients is battery acid.
The series features several powerful drinks with such wonderful names as Troll's Sweat and Djinn Sling. Drinking too much has such effects as knocking you out (at which point you wake up outside the bar with your wallet missing), or outright killing you.
Quest for Glory 1 features "Dragon's Breath", which makes your character spontaneously combust if you drink it. In the fifth and final game, the Dead Parrot Inn has a rotating selection of house special drinks; one is the Dragon's Breath. After four adventures and defeating evil djinns, demons, and an Eldritch Abomination, the hero is finally able to stomach it (but it still turns him fire-engine red and makes him bounce up and down like a Looney Tunes character).
The Monkey Island series of computer games does this to grog. Instead of plain-ol' watered-down rum, it's a drink made with a variety of bizarre ingredients, which may (or may not) include Kerosene, Propylene, Glycol, Artificial Sweeteners, Sulphuric Acid, Rum, Acetone, Red Dye No 2., SCUMM, Axle Grease, Battery Acid, and/or Pepperoni. Needless to say, it's capable of burning holes through reinforced pewter mugs in a matter of seconds. This apparently doesn't stop it from being sold in familiar-looking red-striped soda vending machines, despite the games being set in the 17th century. The unusual composition is no doubt why, in the second game, near-grog is described as being as nasty-smelling and foul tasting as the real thing, sans the alcohol, so even pre-fake-ID Guybrush is allowed to drink it. Or he would be, if the bartender hadn't just sold the last bottle to Captain Kate Capsize, who prefers to be sober when she runs her glass-bottomed boat tours.
In Monkey Island 2: LeChuck's Revenge, one puzzle for retrieving a map piece involved having a drinking contest with a hermit named Rum Rogers, Jr. using his grog recipe, with twice the alcohol and twice the calories. No matter what, Guybrush has to drink first, and drinking it causes him to faint after flipping out. You have to dump the grog into a nearby tree and substitute it for the near-grog before sitting on the stool, therefore accepting the challenge, forcing Rogers to drink his grog and collapse after you have your turn.
Neverwinter Nights allows the player to engage in a drinking contest, with the final round (before the opponent passes out) being a beverage known only as scurrd. It is, from a game-rules perspective, statistically impossible for any normal human being to imbibe scurrd without losing consciousness; it requires a Constitution score one point higher than what a first-level character is capable of having. A character with magically-enhanced or dwarven constitution can safely drink the scurrd, which results in the opponent passing out, and earns the PC massive respect from his buddies. If you successfully drink it, it temporarily doubles your hit points. It's the game world spontaneously recognizing the sheer Badassery of your feat.
Kusuha Mizuha from Super Robot Wars: Original Generation is famous for her "Health Drinks". The exact ingredients are unknown, but what is know is that a single sip is enough to knock adult men unconscious. However, once you recover you feel absolutely amazing. There exists a select few (mostly aliens) who actually enjoy the taste. Most other people run in terror the moment Kusuha offers them a drink, under the cover of flat-out (but politely delivered) Blatant Lies.
On Ryusei's route in the first game, Ryusei actually tries to explain to Giado and the others exactly what it is that goes into a "Kusuha Special" (something having to do with ground-up gecko tails and viper venom). Naturally, this doesn't sit well with Giado or his stomach. Elzam and Arado are among the few human characters who can withstand it. Elzam, being a Chef of Iron, isn't intimidated by so-called "bad food" (he went so far as to name all of the ingredients; granted, it was in the Alpha games, who have almost no translations at all), and Arado's undergone so much gene modification that he can consume almost anything that's generally edible.
Surprisingly, Heero Yuy drank it in Alpha 2 without passing out; of course, he's Made of Iron, so it wouldn't be surprising if he had a cast-iron stomach. Which makes Masaki Andoh's reaction of completely passing out even more hilarious, seeing as how he and Heero share a seiyuu.Divine Wars follows up on this for more hilarity: After using a Cyflash to take out the Divine Crusaders' enemy forces at Aidoneous Island, he is exhausted due to how Cybuster's attacks work (long story). Since Cybuster is still needed, Shiro and Kuro produce a bottle of Kusuha's health drink; Masaki immediately recovers in order to avoid the health drink. Even aliens who happen to be stone-cold badasses are not necessarily immune; Ingram had a few moments of what must have amounted to an alien version of "oh god oh god I'm gonna die". Although, the Divine Wars version of this incident had Ingram sound like hewas havinga giant orgasm.
Lamia Loveless, an android, is incapacitated by the drink. Her first assumption is that they found out she was a spy and tried to poison her. Actually, she suspected as much before drinking it, but was absolutely positive afterwards.
Come 2nd Original Generation, Ing Egret and Ventus said that the drink is delicious. When Michiru Hanaten drinks it, he claims that it's so bitter though he doesn't pass out but that was because it was only a super mild edition.
The game has you construct several of these on various quests. How potent they truly are really depends on what level the quest is, although the quest giver will always act like it's the strongest stuff out there.
The actual Gargle Blaster of the game is the Sulfuron Slammer. It's so strong, it sets you on fire when you drink it.
To quote Harkkan; "Thundermar ale is 220 proof; I don't know how that's possible."note 220 proof is 110% alcohol
Gemstone IV introduced a blackout-inducing drink called Eldreth's Death-rum, based on a real player-made concoction served during a gaming convention room party. Several employees watched as a brave attendee offered to try the stuff, pronounced it "not that bad" and started to walk away with no ill effects — before suddenly dropping to his knees five steps later.
The potion maker in The Legend of Zelda: The Wind Waker uses a welding mask as described above when mixing up new potions. The process also involves small explosions and clouds of colored smoke. Link burps up a small puff of colored smoke after drinking one.
Such as the Pan-Dimensional Gargle Blaster. Drinking it gives you the message "You feel like your head is a gold brick with a slice of lemon wrapped around it."
However, this drink is a failed inversion of the trope. The Pan-Dimensional Gargle Blaster is designed to cause absolutely none of the traditional Gargle Blaster effects; it shunts all of them to an Alternate Self in a parallel universe (hence the name). Unfortunately, it turns out that if you're the sort of person who would drink one, the odds are amazingly good another you will be drinking one at the same time, so...
There are a number of suitably dodgy drinks available in the clan dungeon Hobopolis, including fermented pickle juice, "squeeze"note Sterno with the denaturing additives filtered out and the booze available from the hobo marketplace in the Hobopolis Town Square.
When the MMO Asherons Call added brewing as an Item Crafting ability it became possible to brew "Tusker Pus", a beer so horrible it does 9999 damage when drunk, several times more damage than a player character can possibly have hit points.
If you go to visit the nurse's office in Persona 3 while tired or sick, the whackjob who runs it (who also teaches a class on magic, mind you) offers you a concoction that is made of a number of poisonous substances and some good-luck charms (including rabbit's feet... in a drink). If you choose not to drink it, he gives you actual medicine; if you drink it, it boosts your Courage, because he congratulates you on having the guts to try.
White Gull is one of the few potions The Witcher can brew that isn't instantly lethally toxic to mortals. It can be brewed from any alcohol available, and makes the ideal base for any other potions. Even with his Witcher resistance to toxins, just one will make Geralt drift across the floor like a bobber on a fishing line, two will get him 86'd to wake up on the cobbles. Non-Witcher humans won't get through one. There is no canonical evidence of how much a dwarf can drink. It's sometimes used as an anesthetic on those already near death.
Space Quest 6 and the fan-made prequel Space Quest 0 feature "Coldsaurian Brandy," an extremely potent and disgusting liquor (it has a rotting fish in the bottom of the jug). Roger doesn't drink the stuff, but it makes a mean Molotov cocktail, and it's good for poisoning purposes.
In Atelier Annie, nobody knows exactly what it is in Gillian's drinks, but know that the stench is so powerful it could fell a field of Punies from a mile away, so they (especially Annie and Pepe) don't go near the stuff. Gillian is oblivious to this sort of reaction, and guzzles her own concoctions like water.
Dragon Age: Origins has a list of dangerously potent alcoholic drinks the PC can give to Oghren (or Wynne, though Wynne prefers wine). The only drinks that don't count as gargle blasters are the watered-down ale and the wine. And the brandy. More amazingly, in Awakening Oghren is able to easily shrug off the darkspawn blood (and other mysterious-and-horrible ingredients) used for the Joining ritual of the Grey Wardens with a loud burp, while other characters either pass out and have freakish nightmares or die hideous deaths.
For reference, The Warden, your character, passed out and had the nightmares when s/he undertook the Joining.
The Dark Star bar on the Citadel in the second game serves the Commander "batarian ale - uncut". The bartender has never seen anyone drink it and remain standing. Shepard, of course, orders another one, at which point the bartender gives him/her a ryncol, below. The aftermath of Shepard's binge-drinking in the Dark Star is undoubtedly the most amusing part, with the Commander waking up on the men's room floor sometime later while a turian relieves himself at one of the urinals. Doubly hilarious if your Shepard is female.
Then there's "ryncol", the krogan drink of choice. Said drink is said to have the effect of paint thinner on non-krogan. Shepard is knocked out by it. Then again, Shepard isn't quite humananymore. Grunt's recommendation on ryncol is "Don't try to act tough — that stuff'll go through a human's insides like broken glass." The Darkstar bartender informs you when you order one that you'll be setting off radiation alarms for a week.
Citadel also contains a reference to drinks called turian horosk and a volus bina. Turian horosk is not being served because the establishment wants their guests entertained instead of comatose. A volus bina meanwhile will put you on the floor with its alcohol content while the ammonia will let you clean up after yourself. If you survive.
Citadel also also contains a rather disgusting cocktail that's three parts horse-choker and one part mouthwash, made by Joker for a drinking contest to keep Cortez from dragging him out to the shooting range later. (Joker wins, he doesn't go.) Cortez manages about two shots and gives up from the taste alone, which he poetically compares to a goat's ass.
Yet another one for BioWare: Tarisian Ale in Knights of the Old Republic is brewed with glands from a monkey-like critter. There's an optional sidequest where some low-ranking Sith mooks serve it at a party. You and Carth apparently don't partake, as the two of you are the only ones in the room conscious after the party-goers drink it.
In Nelly Cootalot, the Barnacle Bar offers several drink with questionable names. Things like Texas Medicine and Admiral Nosehair's Old Unsanitary come to mind.
Team Fortress 2 is silent about the composition of the Demoman's "Scrumpy", but general fan opinion is that it's some sort of Gargle Blaster, very likely self-distilled (one of the maps is Granary, and one of the Demoman's teammates is a borderline Mad Scientist Engineer from Texas...).
The description for one item indicates that, even scrumpy not being enough, the Demo has even started drinking woodgrain alcohol.
Brave Soul has a cocktail called the "Lady Killer" which the bartender claims to be almost 100% alcohol. Rudy is knocked out. Alicia claims it tastes like juice.
Final Fantasy X: Whatever is in Auron's jug is not to be trifled with considering in his Overdrive he spits it onto his BFS, which causes dark fire and black holes. Another has Auron creating a whirlwind and then hurling his entire jug in, at which point the tornado turns into a fiery pillar. A level of Fridge Brilliance when it comes to the alcohol: He's already dead, so that's why he can handle it.
The series has a number of alcoholic beverages and narcotics that give temporary benefits to the player, such as increasing their combat speed, making them more resistant to damage, or raising their charisma (one of the amusing side effects of alcohol). There's a Truth in Television moment in that your character can become addicted, and once the effects of the drugs wear off his/her stats are reduced until s/he is either cured of addiction by a doctor, or s/he takes another hit. It's surprisingly fun to play as a junkie.
The Fallout: New Vegas DLC "Dead Money" introduces the "Sierra Madre Martini", created by Dean, a Ghoul who's been in the Sierra Madre for two centuries and had time to experiment. It's created via brewing the residue of the poison cloud that permeates the place with a bag of potato chips in a rusty tin can. Tastes hideous, highly addictive and gives some pretty nifty buffs.
There is but one drink that can beat a Serra Madre Martini... the awesome Large Wasteland Tequila. At 100 survival skill it gives you +9 strength, +3 charisma, and -9 intelligence. (The maximum stat level is 10 and the minimum stat level is 1.) It makes you as strong and as stupid as statistically possible unless you have the Whiskey Rose perk when you drink it. Sweet Jesus.
The player can enter into a drinking competition with what turns out to be Sanguine, the Daedric Prince of debauchery. The brew is apparently strong enough that the Dragonborn wakes up on the other side of Skyrim with no memory of the previous night, having experienced all manner of wacky adventures.
Talen-Jei, the waiter at the Bee and Barb inn, dabbles in making cocktails. The Cliff Racer, a blend of Firebrand Wine, Cyrodiilic Brandy, Flin, and Sujamma, fits this trope closest, but the Velvet LeChance deserves an honorable mention for being garnished with Deadly Nightshade (albeit a nonlethal quantity).
In The Elder Scrolls III: Morrowind, Ancient Dagoth Brandy can be found, and its effects include (semi)permanent reductions to both intelligence and willpower, with no benefits to show for it. Considering the drinks have likely been fermenting in the presence of plague-infested evil for s few hundred years, its potency is understandable.
Bottles of liquor found in System Shock 2 are usually somewhere around 250% proof, but they are graded after effect rather than alcohol content, and contain a number of other drugs that simulate the effects of alcohol.
Heroesof Newerth: One of the Engineer's skill involves throwing a large explosive keg, stunning and knocking back any targets hit. According to the skill description, he drinks this stuff.
In NieR, one sidequest requires you to prepare a special drink for Popola so she can work up the nerve to sing alongside Devola. The bartender says Popola is the only one that can stomach it. The ingredients include lizard tails and rat tails.