So your protagonists are nerds and hobbyists just like their players, and you have to populate the shelves of a little specialty shop the party insists on visiting. You don't need each one to have a fully fleshed-out ruleset like Three-Dragon Ante or Dragonchess, but you still need an idea to run with for each- you just need some names and concepts, and if the PCs bite, you can fudge the rest.
Well, we've got the names and concepts, and you—presumably—have the fudge.
Dvürgfest
Appearance: Frothy beer practically spills out of the box art as dozens of highly insensitive dwarf stereotypes smash their tankards together around drenched wooden tables and roaring firepits. Enormous mouths open in raucous laughter and sausage-like fingers point as one of their fellows coughs during a chugging contest and sends a geyser of aerosolized booze across the scene. A warning label shaped like a slightly off-kilter wooden tavern sign requests the utmost responsibility from any and all players in bolded Sans Liability font.
Back-of-the-Box Blurb: Oi, laddie! Ye look like ye hae a strong stomach. Why don't ye an' yer mates pull up some chairs an' a keg! What are we celebratin'? Why, Dvürgfest ay coorse! It's always Dvürgfest!!!
Contents: 12-page rulebook, 6 shot glasses, 1 reusable writing tablet, 1 fifty-charge wand of Conjure Alcohol with a 50% chance of missing 1d6 charges- the box was tampered with, and either the store manager or a customer abusing the returns policy used the wand a few times.
Prep Time: None, Play Time: Variable, dependent upon the constitution of the players.
What It Is: An Irresponsibly Good Time.
True to its name and advertising, this is a drinking game with little in the way of skill, challenge, or even chance. You pick a game from the book or set your own parameters for sips and shots on the tablet, and then get to work on your night. One player has the distinction of being the "Brewmeister" who keeps tally and uses the wand for refills, but they are not exempt from drinking either. The wand can conjure a small variety of alcoholic beverages depending on the magic keyword spoken while activating it, ranging from a potent pilsner to a highly combustible rum. The wand also has around 50 charges, which is hopefully enough for several games. There is a form and address in the back of the rulebook for ordering wand refills- you may notice the wand constitutes 90% of the cost of the game, and that just getting drinks at the pub would be cheaper.
Consequences: All participants must Save every hour of play or wind up dangerously drunk. Even the "winner" becomes decently tipsy at the end of the game. Any penalties for inebriation are in full effect, and the following morning all participants must Save with disadvantage or else wake up severely hungover.
Capital
Appearance: The letter 'C' explodes off of the box in a font several dozen sizes bigger than any other text on the box, to make sure absolutely no one misses the fact that the C in Capital is capitalized. Disembodied hands rake through a dragon hoard's worth of gold coins and jewels underneath it, surrounded by a halo of industrious vignettes depicting fleets of trade ships, smoking factories, well-to-do gentlemen, statuesque workers striking handsome poses as they labor, etc.
Back-of-the-Box Blurb: Become a merchant prince! Grease the wheels of industry with the sweat of your brow, make daring investments, and live a life of high adventure in high society with your fellow players... at least until you claim it all for yourself!
Contents: Folding board, 216-page manual, 4 sets of obnoxiously nonstandard polyhedral dice carved from the bones of an animal species that has since become critically endangered, 3 twenty-count decks of event cards, 500 building/worker/currency tokens.
Prep Time: 3-4 hours; Play Time: 30 minutes to 2 hours
What It Is: Friendship Ruiner.
The grueling setup time is the result of the game's extensive random generation rules. You don't play in the same world from game to game- each one is created from scratch with its own economic and sociopolitical variables in play. The entire global economy is simulated, with greatly varying degrees of depth and realism therein.
Players, too, have their fair share of prep work. After determining first-come-first-serve turn order, each player generates their merchant prince ("or princess!!", as the rulebook rather proudly declares numerous times, always in italics with exactly two exclamation points). To create a prince(ss), one must also create five generations of family history, fortune, inheritance, and "good breeding" that leave the player with a wealth (or dearth) of bonuses and point modifiers. To cap it off, the merchant begins play with a random starting gift/investment of money and liquid assets. These gifts are determined using open-ended polyhedral dice rolls that can explode multiplicatively, and can often (around 40% of the time) result in a player acquiring most or all of the game's currency tokens, thereby winning the game before play has even started.
The actual game is played on a rather cheap, flimsy board. (Deluxe editions of the game use carved hardwood of questionable legality that raises the price fivefold.) The board depicts the nondescript metropolis of Fortuna, studded with rings and boxes for game pieces and stacks of special event cards. Players compete in several industries while committing corporate espionage or naked acts of aggression against one another and trying to win the local government to their side. Alliances are supported, but they are designed to be fast, loose, and brief. Wealth tokens can be spent on various ventures, or wasted in acts of conspicuous consumption that give you influence points and favors among the aristo-plutocracy, to be spent later for even more wealth.
The final tally is its own game, full of byzantine rules for point calculation dependent upon world-generated modifiers, as well as any changes that occurred over the course of the game.
Consequences: At least one character will develop a deep animosity toward another—most likely the winner, or the most ruthless player—for one day thanks to this game. They must Save or else do nothing to help whenever preventable misfortune is about to befall the target of their righteous indignation.
At-Home Adventure
Appearance: The box's eerily photorealistic cover art depicts a ragtag band of misfits not unlike the PCs, gathered around a table where they are poring over books, reference sheets, and a grid board populated by figurines that resemble miniaturized versions of themselves, albeit markedly different in minor, idealized ways like height, physical appearance, or gender. The figurines seem to be coming to life, animating into flesh and blood out of their former ivory and pewter states to do battle with a group of ruffian figurines undergoing the same transmutation.
Back-of-the-Box Blurb: Enter the battlefields of Imagination!
Contents: 10 meters of grid paper, 5 sets of 6-piece polyhedral dice, 248-page "core rulebook", 129-page "referee's manual", 10 "sample adventurer" brochure-booklets, 100 character sheets, dice rolling tray, privacy/reference screen, 100 paper tokens, catalogue of ~20 optional supplement books available for order.
Prep Time: Meta-variable; Play Time: Indefinite
What It Is: Hyper-Simulationist.
This game so perfectly replicates the "real" world of the campaign that the PCs use the exact same systems and mechanics to play it that you and your players use to play them, albeit with a few terms replaced by suspiciously specific synonyms. The PCs may even create characters who are uncannily perfect twins of themselves. The board game essentially becomes a mesagame- a game within the game whose distinction from "reality" relies entirely upon a thin veil of cognitive dissonance.
Consequences: The entire party must Save or else experience a spiraling existential crisis as they begin to consider the implications of living in a world that can be simulated so perfectly. They can almost hear your dice rolling...