Artifact of Attraction: Shardblades and Shardplates technically don't qualify, since the attraction isn't supernatural, but they're so incredibly valuable the difference is academic.
Artifact of Doom: Shardblades, possibly. Syl mentions that she doesn't like Shardblades, and that Dalinar is a better man for giving one up. According to the Word of God, Syl, an honorspren, is specifically attracted to Kaladin because he refuses to take a Shardblade offered to him.
Shardblades, at least, are explained in the second book: they are the physical form of spren bonded to the old Knights Radiant, and after the Knights broke their oaths they died, leaving the corpses behind.
Authority Equals Asskicking: If a Shardbearer wins an extra set of Shards, he can gift them to anyone he wants— usually an equally noble family member, who will thereby become a badass.
Badass: Many. Any Shardbearer is guaranteed to be awesome by the nature of the armaments. Kaladin and Szeth stand out in particular, and Kaladin isn't even a Shardbearer. Dalinar, on the other hand acknowledged as badass even for a Shardbearer — at least, when he's not holding back.
Words Of Radiance previews reveal that the Second Ideal of the Edgedancers is "I will remember those who have been forgotten."
Also from Words of Radiance the Second and Third Ideals of the Bondsmiths "I will unite instead of divide", and "I will bring men together." and the Third Ideal of the Windrunners: "I will protect even those I hate, so long as it's right."
Battle Couple: Suggested to be the way Parshendi fight. Possibly also an appearance in one of Dalinar's visions; we see two Radiants working in tandem — one male, one female.
Berserk Button: The Parshendi/Parshmen have a race-wide Berserk Button when it comes to others touching/moving their dead. Kaladin figures out a way to exploit this.
BFS: Most Shardblades. Dalinar's and Adolin's are mentioned as being six feet long.
Big Bad: One hasn't actually shown up yet, though given that it's only the first book of ten, this may not be surprising. It is, however, heavily hinted to be Odium.
Roshar is apparently a land without soil, has random seasonal changes every few weeks, and is scoured by hurricane-force storms on a near-weekly basis. Adaptations include grass that retreats into holes in the rock when threatened. Very few, if any, animals other than the humanoid races seem to even be mammals, with beasts of burden and domesticated pets being mostly crustacean, reptilian or insectile.
The Parshendi race has shades of this. We know their bones are red, their skin is marbled red-and-black, their blood is orange and smells moldy, and they grow their armor as part of their bodies.
Also inverted when it comes to the country of Shin. Highstorms don't reach there, so the ecology of the region is a lot more similar to Earth, even to the point of having strawberries and chickens. Visitors to this land from the rest of Roshar find it extremely strange.
Color-Coded Stones: Played with somewhat, where there are ten gemstones used in Soulcasting; each gemstone can transmute a certain element, and the association is based mainly on the commonality of colour between them. In order, with colours and elements listed, the gemstones are: Sapphire, blue, any clear gas. Smokestone, black, any opaque gas. Ruby, red, fire. Diamond, white, crystal. Emerald, green, plant matter. Garnet, rusty red, blood. Zircon, yellow, oil. Amethyst, purple, metal. Topaz, brown, stone. Heliodor, golden, flesh. Word of God is that originally their magic was going to be based on mineral composition, until he realized that most gems are pretty much identical from that perspective, so color is easier.
The Commandments: The Ideals of the Knights Radiant. The Second through Fifth Ideals differ from Order to Order between the ten, but the First remains the same. Breaking them results in the spren involved in giving Surgebinding to the Radiant dying, causing a Depower and killing the Morph Weapon Shardblade made, rendering it incapable of morph.
Cool Horse: Ryshadium horses; bigger, stronger, and smarter than virtually any other breed. They choose their own riders and are apparently very picky; Dalinar estimates that no more than a dozen men have been chosen, out of the hundreds of thousands in the warcamps.
Continuity Nod: There are a number of small references throughout the book to Sanderson's larger multiverse, i.e. the start of Chapter 18 mentions a man named Ati who, in the Mistborn books, was Ruin. Also, the character Hoid.
In Words Of Radiance is heavily implied that Zahel is Vasher. Not to mention Nightblood, who is given to Szeth.
Many, though in particular the anonymous letter excerpts given at the start of certain chapters contain many references to mysterious people, places, and events.
The Old Magic and the precise nature of spren in particular. They're mentioned often, accepted as part of the world... but never truly explained.
Doorstopper: The original title of the second book was going to be The Book of Endless (or Infinite) Pages, until Brandon's editor pointed out that the title might be a bit on the nose for a 1001-page book. As it happens, this second book—which was eventually named Words Of Radiance—apparently clocks in at 1088. Any longer, it would have been unpublishable.
Easy Logistics: Soulcasters can virtually eliminate an army's need for supplies, as they literally create food, wood, buildings, and other such things out of thin air. This makes them every bit as strategically important as Shardblades, and the king's tax on the use of his Soulcasters is Elokhar's main income source.
Spren. There are traditional elemental spren like flamespren and windspren, but there are also spren for certain activities (creationspren for creating art, musicspren for performances), emotions (fearspren, gloryspren), biological processes/conditions (rotspren appear on infected wounds, lifespren appear near health plant life, hungerspren appear around someone starving, etc), and other things (starspren, which look like shooting stars but can change direction; deathspren, a mythological spren that are only visible to people who are very close to dying).
It is strongly suggested that there is a Voidbringer minion connected to each of the Ten Essences, though so far we have only seen thunderclasts (massive, vaguely dog-shaped beasts of animate stone, connected to stone) and Midnight Essence (animate smoke inside a weasel-like skin with sharp teeth and claws, connected to smoke).
Eye Color Change: It is believed by many characters that if a person with dark eyes wins a Shardblade their eyes will become light. Notably Szeth's eyes are normally dark green but become pale blue when he is actively using his Blade, he notes this is unique to his particular blade, so it's not entirely clear what the actual situation is.
In Words Of Radiance, we see Kaladin's eyes turn sky-blue when he speaks the Third Oath of the Windrunners. Also, we discover that Parshendi eyes turn glowing red when they become Voidbringers.
Fantastic Caste System: The Parshendi can shift between a variety of different forms, each of which has its own strengths and weaknesses. Warform is the one we usually see them in, making them big and strong and causing them to grow an armored carapace. Workform is similar to warform, but without the armor and with a mental block against conflict. Mateform is used for reproduction, while nimbleform is generally dexterous and quick. Finally, we have dullform, a baseline form with no distinguishing properties, and slaveform, the mindless state that most parshmen exist in. There's also Stormform, one of their Voidbringer forms, which turns them into hate-filled killing machines that can generate lightning and in large groups can summon an Everstorm.
Fantastic Honorifics: "Brightness" is used to refer to lighteyes in much the same way as "lord" or "lady" would be used for nobility. "Brightlord" is also used, but seems to be reserved for those of much higher rank than the speaker.
Fantastic Light Source: Spheres, which double as money (see Fictional Currency, below). When infused with Stormlight, they glow; the brightness and color of the light depends on the size and type of gemstone, respectively. Diamond spheres make the best light sources, as they're pure white; a mark is almost as bright as a candle, and a broam is several times that — and (unlike candles, lamps, or torches) they don't flicker, don't give off smoke, and last for a week or so before needing to be re-infused. Clear goblets are filled with spheres and used as lamps; "wasting" spheres on light is something of a status symbol.
Fantastic Racism: Between lighteyes and darkeyes, and between Alethi and Parshendi/Parshmen.
Fantasy Counterpart Appliance: Spanreeds are a convenient way to communicate in writing, not unlike texting or a very fast telegram. Spheres, because of their Stormlight, are used in affluent areas as lightbulbs.
Fictional Currency: "Spheres", which are glass beads with gemstones embedded in them. The spheres themselves are always the same size, but the gems inside them come in three different sizes; chips, marks, and broams. Nine different gemstones are used; their relative value is based on their usefulness in Soulcasting (see Magic A Is Magic A, below). To make things even more complicated, sometimes different names are used for the gems. Details Spheres are roughly the size of a person's thumbnail, usually with one side slightly flattened so you can set them down without them rolling away. Chips are the smallest denominations, with just a tiny shard of gemstone; marks are larger, worth five chips; broams are the largest. Different gems used include diamond (the lowest), garnet, sapphire, ruby, and emerald. We're never given exact conversion rates, but it seems to work in multiples of five. Their alternate names are descriptive; diamonds are "clear", garnets are "blood", sapphires are "sky", and rubies are "fire" — eg, a clearchip is a diamond chip, a firemark is a ruby mark, etc.
High Fantasy: Sanderson has described the series as his "love letter" to the genre.
Hive Mind: It seems that the Parshendi have something like this. They have an uncanny ability to sing in time and in tune with each other... even when out of earshot.
Hollywood Tactics: In-Universe example. The Alethi use these constantly. Despite the fact that the ostensible purpose of the war is to punish the Parshendi for murdering the king, the Highprinces are mainly concerned with hunting the beasts that provide them with gemhearts and the wealth they represent, and only fight against the Parshendi when it's necessary to reach the plateau where the beast is spotted or withdraw back to their camps after claiming the gemheart. Dalinar has noticed this and is trying to turn the campaign into an actual war.
Hostile Weather: The highstorms. They strike every few days, blowing from east to west, and are so powerful that being out unprotected in one is literally a death sentence. They've also scoured all dirt and soil from the eastern half of the continent (leading to some bizarre plants and animals), and bring the mystical Stormlight that powers everything.
It's Raining Men: According to Dalinar's visions, the Radiants could arrive for battle this way.
Jackass Genie: The Nightwatcher, who will grant seemingly any wish, for a price. In fact, most people who go to the Nightwatcher end up regretting it. The only person (we've heard of) who didn't was one man who made his wish to feed his family through a harsh winter. His curse was that he literally saw the world upside-down for the rest of his life. It was weird, but he got used to it. For Dalinar, the Nightwatcher erased all his memories of his wife. He can't remember anything about her except that she existed, and whenever someone speaks her name, all he can hear is static. As of The Way of Kings, it's unclear whether this is his curse or his wish.
Language Equals Thought: Averted. In Alethkar, the lighteyes are the nobility, and the darkeyed version of Alethi doesn't appear to treat them as separate concepts. Rock runs up against this when trying to talk about how nobility works in other countries, but no character shows any particular trouble recognizing the idea of lighteyes not being on top.
Literal Genie: Subverted. One character thinks that the Nightwatcher works this way, and plans to word his request to her carefully enough that it doesn't backfire. His friend informs him that this isn't how the Old Magic works, though; the Nightwatcher will grant you your wish just like you wanted it, but she will also place a curse on you which she feels is equal to the wish's value. Sometimes the curse makes the wish ironic, but it's often completely unrelated.
Lost Technology: Shards. Scholars have been trying to replicate them for as long as anyone can remember, but only recently has any progress been made in the form of "half-shards"; shields that can block a shardblade, but don't grant any of the other benefits of Shardplate.
Navani notes that the half-shards aren't actually progress towards Plate, since as far as anyone can tell they use a totally different mechanism.
The revelation in Words Of Radiance that Shardblades are actually transformed spren explains why the artifabrians have had so much trouble with them.
Kryptonite-Proof Suit: The Lashings (and presumably all other forms of Surgebinding) can't be directly used on Shardplate or its wearer.
Magic A Is Magic A: There are at least two different (though related) systems: fabrials and Surgebinding. Fabrials are a form of Magitek: by trapping a spren in a gemstone and providing it with Light, you can force the spren to do whatever you designed the fabrial to do, from emitting warmth to telekinetically synchronizing two objects to turning rocks into (bland) food. Surgebinding is granted by the Nahel bond, a link between a human and a spren whereby the spren gains sentience in the Physical Realm and the human gains Surgebinding powers. All Surgebinders can inhale Stormlight to gain enhanced strength and speed and a moderate Healing Factor, but each order can also use the Light to accomplish specific magical effects. So far we know some or all of the powers for five orders:
Windrunners gain Gravity Master powers, allowing them to redefine "down" at their discretion. So a Windrunner can decide that gravity now pulls them forwards or up or sideways, and they will fall in that direction. Or they can make an enemy fall straight up into the sky. Windrunners can also increase an object's gravitional pull, allowing them to pull arrows out of the air and into a shield or bridge or whatever. Finally, Windrunners can also fuse together two objects with a temporary but virtually unbreakable bond.
Lightweavers gain Soulcasting, the ability to transform one substance into another (such as turning a bandit's body from flesh to glass or turning rocks into food or a goblet into blood). They also can conjure incredibly detailed illusions, complete with sounds and motions.
Magic Knight: The Knights Radiant in the backstory. Szeth and ultimately Kaladin during the main novel.
Magitek: Fabrials, which are essentially steampunk-type devices which run on Stormlight, and are used for a variety of purposes, including Soulcasting. Though Jasnah and Shallan don't need them to Soulcast. Shardplate and Shardblades represent a much more ancient and advanced form of Magitek, though the secrets of creating them have been lost (not that people don't try).
Mana: Stormlight functions like this when used to directly power magical abilities.
Man Child: One of the Ten Fools, Cabin, is mentioned to have behaved like a child even though he was an adult.
Medieval European Fantasy: Odd subversion. The Alethi and related cultures at first seem to be this, with their knights and castles and lords and so forth, while other cultures like the Shin seem like Wutai. But then there's an interlude where we actually visit the Shin lands, and in fact they are much more 'normal' feeling to the reader because they have fertile soil and plants that are familiar to us (such as strawberries and non-motile grass) but treated as exotic and alien by the Alethi.
To play with this even more, according to Word of God the Shin are the only race on Roshar that don't have "Eastern" almondine eyes. It's noted to give the Shin a "childlike" appearance.
Medieval Stasis: The Desolations are a direct cause of this. They are so destructive that civilization is often totally broken by the time they end, to the point that the Heralds won't even be sure if the next civilizations can forge bronze when they show up to fight the next one. However, the Heralds' abandoning of the Oathpact at the start of the first book and the Parshendi's abandoning of their gods appears to have delayed the Desolations long enough for a rather advanced set of societies to develop.
Nature Spirit: Some spren seem to fill this role, though many others instead seem to either be attracted to or created by intense human emotion.
No Pronunciation Guide: Brandon Sanderson pronounces the J in "Jasnah" as a Y, as if it were a Scandanavian name. There is nothing in the book that indicates this should be the case.
Oh My Gods!: "Stormfather!" and "Living Heralds above!" are both commonly used as exclamations. Also, "Damnation" is used in place of "Hell", and if you don't like someone you tell them to "Storm off."
The Order: The Knights Radiant, founded by the Heralds. The Knights Radiant were actually divided up into ten individual orders (even called such in-universe), though all of them seemed to be Shardbearers. Word of God says that each order had two types of magic like Soulcasting or Surgebinding (see Magic A Is Magic A, above) and each of those was shared by two orders (the diagram on the inside front cover of The Way of Kings illustrates this).
Our Nudity Is Different: The cultures based on the Vorin religion consider a woman with her left hand (the 'safehand') bare to be provocative. Commoner women wear a glove to cover it while noblewomen wear dresses with left sleeves that cover the entire arm and hand and button shut. At one point we see a prostitute, who wears a short-sleeved dress, and Kaladin cannot take his eyes off her safehand.
People of Hair Color: Certain nationalities have hair colors strongly associated with them — black for the Alethi, red for the Vedens, and gold (not blonde, but actual, shimmering gold) for the Iriali. You can even tell people of mixed nationality, because they usually have multicolored hair in streaks.
Photographic Memory: Bizzarely literal example with Shallan. She can, by blinking, take a Memory of a scene, which allows her to later reproduce that scene with photographic accuracy, including showing the otherwise invisible Cryptics. In addition, when she sketches a Memory, the Memory is gone, leaving her with only a regular memory of the scene. Words Of Radiance implies that most if not all Lightweavers possessed this ability.
The Shin are basically the complete inversion of the Alethi. They consider warriors, "those who take," as the least of their society, and treat them as slaves. Farmers and the like, or "those who add," are given the highest position, since they are contributing to the world. Although never stated outright, one would assume they likewise hold their women in very high esteem.
Also the Thaylen culture appears to be heavily mercantile, most of the Thaylens we see are merchants, and Kaladin's father mentions that every Thaylen he ever met tried to cheat him.
Proud Scholar Race: Thanks to the strict gender roles of the Alethi (and the Vorin religion in general), Alethi women are like this, while their male counterparts are closer to a Proud Warrior Race.
The Alethi deconstruct it; most brightlords are more interested in looking the part than living it. In addition, many Alethi have the "Thrill," a form of bloodlust that grips them in battle, and they've become so glory-hungry that they consider even thinking about peace cowardice.
Self Healing Phlebotinum: Shardplate armor can be fixed, even if a piece of it is shattered, by installing gemstones infused with Stormlight. The gemstones usually crack in the process. And like a starfish, if you have only one piece, you can eventually regrow the whole Plate, unless someone else has a larger piece and is doing the same thing.
Stay in the Kitchen: The Alethi and related cultures (i.e. most of the people we meet) have this for both sexes—only men are permitted to be warriors, but only women are permitted to be scholars (unless they join the ardents), and it is taboo for a man to be literate; men are only expected to know the simpler ideogrammatic glyph system rather than the alphabet. In terms of a person's Calling, it seems to boil down to men being physical and women being creative and/or scholarly. Although it gets into even weirder territory with safehands and the fact that they're not even supposed to eat the same food.
Summon to Hand: Shardblades work this way; they literally vanish into thin air when released, and appear in the owner's waiting hand ten heartbeats after they decide to summon it. (Literally; someone whose pulse is racing can call their Shardblade faster than someone who is calm and collected.)
Technicolor Eyes: The Alethi (and most of the rest of the continent) are split into "darkeyes" and "lighteyes," based (obviously) on eye color. The lighteyes are the rulers, and their eyes are things like gold and violet and white in addition to more mundane colors like blue and green (although dark green is a darkeyes color).
Tron Lines: The Knights Radiant have them in one of Dalinar's flashbacks, right down to the colors — either blue or gold for the two Orders we've seen. Implied that the other orders will branch out into whites, greens, and reds, though what color the Skybreakers (whose gem is black) will be is anyone's guess.
We Need a Distraction: It is implied in Words of Radiance that all of Roshar is one giant distraction to keep Odium from killing anymore of the Shards like he did with Honor, Dominion and Devotion.
World of Badass: Unless you live in Shinovar, you have to contend with Highstorms, Shardbearers, brigands, hostile terrain, and huge monstrous fauna. Generally, you either die, get sold into slavery, or man up and rise to the occasion. Sometimes you get to do all three.
You Kill It, You Bought It: The ordinary way to obtain Shards. Whoever strikes the killing blow on a wielder gets to take the Shards for himself. Note that this is more social convention than anything to do with the Shards - Kaladin refused to take up one he earned in combat, in his backstory, and someone else took it instead.
Mostly shows up with the people of Shin versus those from most other countries. For example, the Shin people value humility above all else (to the point that their trade negotiations consist of merchants downplaying the value of their goods rather than exaggerating them) and consider walking on or otherwise touching or damaging stone to be disrespectful. After travelling throughout the other lands, Shin viewpoint character Szeth reflects that it's rather hard to hold foreigners to these rules considering their lands don't have soil covering the bare rock.
The Horneaters have a caste system based on the order in which children are born, which defines their vocation. When Rock explains this to the other bridgemen (mostly from Alethi-related cultures), the oddest part to them is that the Horneaters do not consider being a warrior to be the highest and most respected vocation. Rock also stuns the others by saying that Horneaters consider long-ranged weapons better and more honorable (whereas among Alethi, there's a reason the officers get swords and the grunts get spears).
Crosses over with Deliberate Values Dissonance, but this is also true of the general culture we see with the Alethi and related peoples compared to the readers. For example, how literacy is restricted to women.