Armed and Dangerous, an obscure but fun shooter for the X-Box and PC, had this... like... a lot. Perhaps the worst offender is the Emperor's retarded son, and I mean actually retarded, who has trouble stringing syllables together. Don't get him started on whole sentences.
The Scout in Team Fortress 2, being the youngest and most hyperactive of the nine classes, has this in a bunch of his domination lines. For example, to the Heavy Weapons Guy: "I am owning you, you fat bald fatty fat... fat-fat!" or to the Sniper: "You'll never hit me! You'll never hit my tiny head! It's so tiny, I've got a frickin'... such a tiny little head!".
Travis from Silent Hill: 0rigins, getting more and more peeved about being dragged around Silent Hill by Alessa, holds up a piece of the Flauros he found and yells out: "I got your... your thing for you!"
When Monkey Island got voices, Dominic Armato added this trait to protagonist Guybrush Threepwood.
"There are ants crawling all over it." "There are other ants crawling all over it."
In the sequel, Hawke sometimes falls into Buffy Speak if s/he tries to lie. Telling Ser Roderick that Hawke saw Conrad sacrifice a goat leads to Hawke stammering "He was talking about how he wanted to do all kinds of... demony things!"
Also when Hawke first learns of Anders ability to Hulk Out into Justice;
In Crash Tag Team Racing, a Park Drone in the Tyrannosaurus Wrecks area, frustrated with Crash for not getting him enough money to leave the park, will exclaim "Again, you come back to haunt me?! Like some kind of haunting thing?! Haunting... and coming back?!"
Mass Effect: Even Commander Shepard is not immune to this... after three hits of the strongest drink on the Citadel, followed by under the counter batarian ale, the bartender offers a krogan drink known as Ryncol.
Grunt, being essentially a krogan teenager, often speaks like this, while trying to either puzzle through his tank-imprints or simply talking outside of combat. On Korlus, the squad will also encounter another tank-bred krogan who is even less experienced and articulate than Grunt, who speaks this way. Though he's also intelligent enough that he switches between this and Sesquipedalian Loquaciousness quite often.
Grunt: We should get behind... stuff.
Jack, at one point, defines the Collectors as "fucked up...bug thing[s]". She's not wrong, exactly...
The Power Punch item description: "Boosts your partner's Attack power by adding buffness".
In Super Paper Mario, the villain Mimi constantly uses childish phrases, referring to the heroes as "meanies".
In the 2010 Medal of Honor, Tier 1 operators look and sound a lot less professional than the soldiers in the normal army, though obviously they're much more deadly. In Running With Wolves you're told to "stay stealthy."
Golden Sun: The Lost Age: At one point, Kraden amusingly refers to a ship-powering crystal as "the thingie... that makes it go." Proving that the Lemurians' Magitek is exotic to him despite his lifelong studies of such.
One item-of-the-month in Kingdom of Loathing allows you to temporarily turn into a vampire, at which point one option during exploration lets you meet an obvious Buffy parody, who calls you "Broody Von Stoicpants", and states that she's "a sucker for a brooder. Broodie? One who broods."
Tales of Graces has one character who is exceptionally prone to this in Pascal. Every other technologically savvy character is prone to just keeping the language simple enough that Asbel and crew can keep up. Pascal, on the other hand, gets an example of this every hour or two.
I Miss the Sunrise has a single instance: Marie refers to the FOCS construct as a "big spinny ring thing" at one point when talking to someone who didn't know its actual name.
Arthur: I just go "Zoom!" and it goes "Whoosh!" and then "Bam!" and the enemies are like "Noooooo!" and I'm all "Hahaha!"
Surprisingly, the normally fustian Asura of Guild Wars 2 has one of these for the female characters. When attacking an enemy, occasionally she'll blurt out: "You're dumb. You'll die and leave a dumb corpse."
League Of Light, an unreleased Activision game for the Intellivision, is described by a reviewer of Digital Press as being "some sort of 3D perspective tunnel-traveling thingus."
In Anna's Quest the title character, who's somewhere around five years old, talks like this from time to time, from referring to a cut-up ball as "half a rubber thingy" to finding a "glowing orb thing" in a drawer.
In Evolve, Val slips into this on occasion while trying to warn the team about Shear's rather bizarre wildlife. She has particular difficulty with the mammoth birds, calling them "glowing... squid things" and muttering about whether they're birds if they don't fly.
Rippers from Metroid have also been affectionately dubbed "That one bug that looks like a croissant that you can freeze and use as a platform", with the name sticking due to the sheer audacity and specificness of it.
An optional cut-scene in Atelier Lydie & Suelle: The Alchemists and the Mysterious Paintings with Lydie and Sue involves Sue entering the atelier to discover that Lydie has synthesized a bomb. She calls it a "burning boom boom" and then Lydie shows her an ice bomb which she says should be called a "Freezy McFreezeboom," and a lightning bomb a "Shocking Blasto." Lydie says that she's losing her, as there's not even a logic to her naming conventions. She worries that Sue is taking after their father, but Roger says that's wrong, and there's a flashback of Honnete suggesting to Roger that a bomb should be named a "Hottie Boomster" and a craft an "Uni Buster." After the flashback ends, Sue pulls out a craft and suggests the exact same name. Lydie actually likes that one, and Roger realizes that Honnete's spirit lives on his daughters. "Some of the weirdest parts of it, anyway."
Barbarian Hero Amiri from Pathfinder: Kingmaker uses very simple language and tends to go into buffy-esque tangents when trying to explain concepts that she lacks words for. It's implied the setting's Common Tongue (Taldane) is her second language, and the party later meets a barbarian from a neighbouring tribe to her own that speaks much better Taldane due to his long mercenary career.