ArcHub: Gaming
FMHY.net/gaming - free gaming directory.
LibreGameWiki.org - the free gaming encyclopedia.
FOSS Games
Awesome open source games [website]
Awesome game remakes [website]
Luanti - Like minecraft, but better
Cataclysm Dark Days Ahead - impressively realistic survival crafting post-apocalypse RPG/roguelike
Mindustry [app] - real-time strategy, factory management, and tower defense game developed and published by Anuken
One Hour One Life - a survival massively multiplayer online game developed and published by Jason Rohrer. Each player lives for, at most, 60 minutes in a large, persistent world, with each minute representing a year of life.
Friday Night Funkin - rhythm video game developed by The Funkin' Crew Inc. and released on Newgrounds in 2020
The Dungeons of Moria - computer game inspired by J. R. R. Tolkien's novel The Lord of the Rings. One of the first roguelikes, developed in 1983
FreeCiv - empire-building strategy game inspired by the history of human civilization
FreeChess - Play chess on the web for free
Space Station 13 - multiplayer sandbox simulation
0 A.D. - a real-time strategy video game by Wildfire Games. It is a historical war and economy game focusing on the years between 500 BC and 1 BC.
Bobball [app] - Jezzball clone
Anarch [app] - Suckless Doom clone
OpenTTDOpenTTD.org [website] - simulation game based upon Transport Tycoon Deluxe
Lexica [app] - timed word-finding game
Pinball [app] - Simple Pinball game with bold, minimalist vector design and atmospheric sounds
BlockDrop [app] - Tetris clone
Kumquats [app] - Scrabble Clone
FOSS Game Engines
GoDot - free, open‑source game engine
Solarus - free, open‑source lightweight 2D game engine
OpenSurge2D - free, open‑source lightweight 2D game engine
Emulators
RetroArch.com - RetroArch is a frontend for emulators, game engines and media players. Among other things, it enables you to run classic games on a wide range of computers and consoles
DuckStation.org - a PS1 Emulator
PPSSPP.org - a PSP Emulator
DeSmuME.org - an NDS Emulator
Dolphin-Emu.org - a Gamecube & Wii Emulator
Miracle - a Javascript Sega Master System emulator that runs totally inside your browser
JSNES.org - A JavaScript NES emulator that runs in the browser
Game Launchers
Tabletop Gaming
Octgn.net - a virtual table top with an integrated player lobby and chat system that supports custom card and board games.
DiceCloud.com - Auditable, real-time character tracking for Dungeons & Dragons 5th edition
Game Tools
fmhy.net/gaming-tools - free game tools directory
Controlloid - Turn your smartphone into a wireless gamepad
SystemRequirementsLab.org - Here is the answer to "Can I run this game on my computer?"
Moonlight-Stream.org - allows you to play your PC games on almost any device, whether you're in another room or miles away
OpenGameArt.org - free game art & assets
MyAbandonware.com - download video games from 1965 to 2014 for free
Other
OpenGameArt.org - free game art & assets
Native Linux Games Collection [software]
Game-Icons.net [website]
A growing collection of SVG icons aimed mostly at video games