Nexuiz is a 3d first person shooter (FPS) done in the old Quake 1 style of gameplay where graphics weren't as important as was the raw fun of pure deathmatch play. That form of gameplay has been lost in many ways in the newer games of today with their greater concentration on graphics and less on gameplay.

Assault Cube is a first person shooter based on the Cube engine. It has a single player mode and multiplayer. This FPS is realistic and team oriented.

In this article I'll overview Cube 2: Sauerbraten, an open-source shooter running on Linux, which also provides a gaming engine for developing FPS games.

AssaultCube is a first-person shooter game based on the Cube engine with support for online multiplayer and single player games, with a fast-pace gameplay and entertaining gaming modes. The latest version was released on November 14, 2010 and brings several bug fixes and tweaks.

Gameplay 1.2, a cross-platform, C++ game framework designed for learning and writing mobile and desktop games, has been released. Gameplay is an open source project hosted on Github and developed by Sean Paul and Steve Grenier, both graphics and game developers at Research In Motion, maker of the BlackBerry® smartphone and PlayBook tablet computer.

"The proprietary game "Minecraft", which is written in Java, may have been inspired by Sauerbraten (also known as "Cube 2")."..."Minecraft and Cube 2: Sauerbraten have a lot in common, if you put gameplay footage of both in front of someone who has never played either, I think that person would think they are the same game, well, maybe without Minecraft's pixelated textures."

Gameplay is an open-source, cross-platform C++ game framework from BlackBerry developers.

Open Arena is a Quake 3 style First Person Shooter built on the GPL licensed Open Source Quake 3 engine. It's a stand alone game, so you don't need Quake 3 Arena to play it. Just like Quake 3 Arena, it's a full on, 3d FPS done in the traditional deathmatch style.

Alien Arena 2007 is a free/open-source first-person shooter game based on source code released by id Software. Started by COR Entertainment in 2004, the game combines a 1950s-era sci-fi atmosphere with gameplay similar to the Quake, Doom, and Unreal Tournament series. Alien Arena is primarily an online multiplayer action game, although single player campaigns are also available against bots.