Half-Life: Source (2004): Resonance Cascade begins

Stupid Stupid Mod — a humorous mod for FlatOut 2 that replaces car sounds, some textures, background video in the menu, visual effects, and adds a new soundtrack, making the game a bit crazier.

A mod that randomizes almost everything in Half-Life, making each playthrough unique. Instead of the familiar crowbar, you might get a Hivehand, and a harmless headcrab could become a deadly enemy. Anything is possible - no matter how many times you return, you'll never predict what's around the corner.

Half-Life: Vertigo Mod is a total conversion of Half-Life on the GoldSrc engine, recreating the atmosphere of the cut "Vertigo" level from Half-Life 2.

Half-Life: Sudden Invasion is a remaster of the cult mod Half-Life: Invasion that improves graphics, interface, mechanics and reworks maps.

OpenRA is an open-source engine that recreates classic RTS games from the Command & Conquer series and Dune 2000. It rewrites the original engine from scratch, supports modern operating systems, online multiplayer, improved graphics and modifications, but requires the original game files for full functionality.