What are some cheap/affordable games you'd like to see more people play?

Are you referring to modern games? As there are plenty of older titles now priced in that range, it simply becomes a case of "did you play it" or not.

Old: Beyond Good and Evil
New: Papers, please

agreed with Mini Metro but people should try this Two Worlds especially if you want to experience true RPG

LiEat, Alicemare, etc...

Here are some of the cheaper games in my library that I've played and would recommend at full price. Getting them on sale is a bonus :)

The Deed - $0.99
Fox and Flock - $1.99
Gunman Taco Truck - $1.99
Hiiro - $2.99
IMSCARED - $3.99
Ahnayro: The Dream World - $4.99
Time Gentlemen, Please! + Ben There, Dan That! (Two games bundled) - $4.99
Pony Island - $4.99
Organ Trail - $4.99
Crazy Plant Shop - $4.99
Rituals - $4.99
The Curse of Monkey Island - $6.99

Edit: I thought this was only a "recommend cheap games" thread rather than a "I want more people to play this" thread.

To The Moon
Tales of Maj'Eyal

Hexoscope — Awesome randomised puzzle game with even more awesome music.
Dominique Pamplemousse — A musical point 'n' click with some message-hammering issues and a cute claymation style.
Robot Legions Reborn — A well-made twin-stick shooter that tests some real veterans as well.
12 Labours of Hercules series — One of the best time manager series of recent times, despite the lack of story.
Windosill — Just a simple, short, but interesting-looking puzzle-ish game.
Don't Disturb — A really touching tale about mourning, mostly told in visuals (the translation is terrible).
Time Gentlemen, Please! and Ben There, Dan That! — Two adventure games with ultra-minimal graphic and full of 100% British humour. The second one is difficult as balls as an adventure game, like in the early 90s.
McPixel — If you like really absurd stupid humour, this will be the best purchase you ever made.
Hamlet or the last game without MMORPG features, shaders and product placement — A very short puzzle game with a unique art style and story.
The Franz Kafka Videogame — SImilar game from the same developer, but this time adding a lot of surrealism (well, it is about Kafka, duh!).
The Blackwell series — One of the highest-rated indie pixel point-and-click series of recent times, following a mystic journalist/detective who can see ghosts.
Poker Night 2 — Still the best poker game on PC, despite being half a decade old.
Marlow Briggs and the Mask of Death — God of War, but with humour instead of constant angst. And lots of explosions. The explosions are important.
The Tiny Bang Story — An incredible cute and charming hidden object style game that mostly sells with its wonderful visuals.
Oknytt — A stylised adventure game based on Norse folklore and a great narration.
Apocalipsis: Harry at the End of the World — It is a little like Oknytt, as in following a stylised visual theme and telling a simple story of your protagonist traversing a strange world, but this is intentionally more macabre instead of being like a campfire tale.
The Room — A game about mechanical puzzle boxes. Incredibly intricate and well-made puzzle boxes.
BasketBelle — A cross between a puzzle-platformer and an art experiment. The second stage is terrible, but if you survive it, the atmosphere should suck you in immediately.
Tengami — Technically a linear puzzle/adventure, but more like an origami tale. The art style sells it.
Gomo — A textless adventure game that follows the style of Amanita games.
Belladonna — A pulp horror tale about waking up as a mechanical zombie and finding out what happened to you. A lot less creepy/gory than it sounds, it is more like an adventure game about personal tragedies.
Detective Grimoire — A mobile point adventure/puzzle game that follows the style of a Saturday morning detective/adventure cartoon with all associated humour.
Milkmaid of the Milky Way — A pixel art adventure game written in limericks, where one of the interesting thing about it is how down-to-earth its tone remains despite being a pulp sci-fi.
The Samaritan Paradox — A realistic (more or less) thriller in the form of a pixel art point 'n' click. Focusing more on the talktaive style of investigation than item combining and chase scenes.
Finding Teddy — A puzzle game with a Metroidvania-ish level setup and a large dependency on musical puzzles (since not a single word is uttered in it). Has a really touching story about a little girl entering a scary world to save her toy. Has some really zany endings if you manage to unlocks the stupid hard hidden NG+ puzzles.

This is what I found in the under-10€ segment.

Side note: I really like heavily story-based games, which is a theme in pretty much all of the below.

A Normal Lost Phone - A casual story-based game where you...snoop in someone's phone

Thomas Was Alone - Lots of platforming and all the characters are shapes but very well-written shapes with varied personalities.

To The Moon has gotten quite a bit of recognition, but everything by Freebird Games is so beautiful. They made the less popular A Bird Story and Finding Paradise.

The Beginner's Guide is also a really interesting experience I haven't had replicated in a game since then. Comes from the creator of the Stanley Parable.

TWD: Michonne was something I personally found enjoyable, but it kind of fell flat compared to the other Walking Dead games. I understand some reasons as to why, but I think I'd like to see more people play it still.

Annnd finally, not as cheap as the others, but I have to mention it: Hustle Cat.

I got it in a Humble bundle this past year for a few bucks and didn't think much of it at the time. I don't remember why, but I decided to play it (probably because of all the cats) and it's remained one of my favorite games since.

Sheltered, Hidden Folk, Last Hope TD, Beholder, Domina, Reigns, Runestone Keeper, Terraria, Tropico 2. Besides Terraria those other games are imo underrated.

There was a thread a while back about games in the $1-3 range that would probably interest you! I can't seem to find it right now.

There are plenty of good games in that price range, but in terms of ones that don't get a lot of love:

The Sea Will Claim Everything Is it because it has too much reading? Because people can't see past the hand-drawn art? Either way, when I give this as a gift people adore it, and yet I've never met anyone outside my giftees who's played it.

LOCALHOST A game in which you're in charge of deleting AI. Every hard drive has its own personality, and its own method of trying to convince you not to kill it. It's up to you to decide what to do.

Hello Charlotte This series gets better with every episode. RPG Maker horror at its finest and most personal.

The Edgelands Poor gameplay, mixed with incredible atmosphere and even more incredible words. Loved this weird little gem.

Yet Another Zombie Defense
It's $2 and had been free once before. A good Co-op game. You can play online with strangers so I hope more players are on the servers. You can carry the game if you're really good at killing/defending against zombies while others are dead during the stage, which is similar to L4D2.

Why Am I Dead At Sea - 16bit murder mystery with multiple endings
LISA - A much darker Earthbound-like rpg