What are your current top.. 5? 10? (dealer's choice) favorite free or currently-free games in your library?
Y’all have really got to get into the habit of specifying whether you mean tabletop games or video games -- ordinarily I just delete the requests that don’t. You’re lucky I have some time to kill!
(Note: several included titles are donation supported or pay-what-you-want rather than strictly free; while you can still get them for nothing, I encourage you to toss in a few bucks if you’re able!)
First, video games, in no particular order:
Dead Horizon - A micro-VN (with some reflex-based minigames) about an infamous gunslinger fighting her final duel with Death Himself; the entire story is framed as a series of flashbacks that take place in the moments before the fatal draw.
ERROR: Human Not Found - An educational investigative VN with puzzles revolving around basic computer science principles. You play as a scientist investigating the murder of the first AI to inhabit a physical body -- a murder in which she herself is implicated.
Gravitas - Yes, it’s a blatant Portal clone, right down to the basic framing device. It just happens to be a really good Portal clone. Here the puzzles are based on gravity manipulation, with the usual mix of environmental problem solving and light platforming.
Heroine’s Quest: The Herald of Ragnarok - A hybrid of a point-and-click adventure game and an old-school Western CRPG where the puzzle solutions can vary based on your character’s build. Some survival elements, though they can be turned off in the difficulty settings.
Her Tears Were My Light - A short romance VN about Time (the player character) courting Space. Has an interesting meta conceit where the player’s “undo” button is diegetically framed as Time’s ability to experience all of history simultaneously.
Khimera: Destroy All Monster Girls - Probably the best Mega Man retroclone out there that isn’t Shovel Knight, if you can get past the cute-monster-girls-beating-each-other-up premise. Less horny than that description makes it sound (though it’s still a little bit horny).
LunarLux - This is the only entry on this list that’s not a full game -- it’s actually a donation supported proof-of-concept demo of a title currently in development. It’s a very good proof of concept, though, with about 90 minutes of gameplay and reasonable replayability.
Overclocked - A precision puzzle platformer in the same general mould as Celeste, with a nice mix of robot-punching and transhuman philosophising. The accessibility features are a bit weak, but there’s only so much you can criticise when the price is zero.
Princess Remedy in a World of Hurt - A short retro RPG (and here I mean retro as in ZX Spectrum, not as in Nintendo) where you play as a magical princess who can cure diseases by entering people’s bodies and fighting their ailments bullet hell style.
Roller Riot - Basically a One Finger Death Punch clone, except with a roller derby aesthetic instead of the usual kung fu movie shtick. There isn’t really much of a sales pitch for this one -- either you’re a fan of two-button brawlers or you’re not!
(Honourable mentions to go A Raven Monologue, Atma, Down Ward, Helltaker, Himno, Honey Rose: Underdog Fighter Extraordinaire, MANDAGON, Perspective, Saira and Wienne.)
As for tabletop games, again in no particular order:
Anima Prime - A game in the style of media like RWBY and Final Fantasy XIII. Does some interesting things with representing tactical positioning via linked, wagerable resource pools rather than by using maps and miniature figures.
Ironsworn - A logistics-heavy travel focused RPG inspired by Scandinavian folklore. Notably supports solo play and GMless two player co-op in addition to the conventional GM-managed setup (which it refers to as “guided” play).
Lady Blackbird - A pamphlet-size system, setting, and scenario in one, casting the players in the roles of a fugitive noblewoman and her crew on a journey to meet a notorious pirate. Another take on wagerable dice pools, this time with fewer explosions.
Mist-Robed Gate - A wuxia psychodrama that is, to the best of my knowledge, the only published tabletop RPG whose conflict resolution mechanics use an actual, physical knife; the text advises playing on a surface you don’t mind stabbing.
Perfect Unrevised - A psychological horror game about heroic criminals in a pseudo-Victorian authoritarian police state. Uses a rotating GM setup whereby each player serves as the face of the Law for another player’s criminal.
Pokéthulhu - A Lovecraft-meets-Pokémon game that honestly does a better job of bringing monster-taming to the tabletop than most serious efforts. Manages to wring a surprising amount of information density out of a dice-rolling mechanic that doesn’t involve any math.
Sufficiently Advanced 2nd Edition - A transhuman space opera game where a city-size hivemind or sapient starship is a valid starting character concept. Makes heavy use of player-facing plot mechanics to balance spotlight time between characters of very different scales.
To the Temple of Doom - A rotating-GM game where the players take on the roles of heroic archaeologists trying to defeat an ancient curse, taking turns making up death-traps for the other players’ characters to overcome. Also check out the publisher’s other free titles.
Unbelievable Macho Bullshit - A GMless, adversarial 80s action movie pastiche where the players take on the roles of evil masterminds, competing to be the last one standing in the face of one-liner-spewing action hero’s unstoppable rampage.
Wushu - A martial arts action game where the size of your dice pools is based directly on how florid your narration is. Arguably more of a guided freeform storytelling exercise than a proper tabletop RPG, but my post, my rules!
(Honourable mentions go to Blowback, Engine Heart, Fate Accelerated Edition, Honey Heist, Lasers & Feelings, Mythender, Poet Glorious, Risus, Sea Dracula -- technically not free, but only costs one dollar -- and Stars Without Number.)