Sci-Fi

Sci-Fi themed games are games that are characteristic of science fiction literature; the narrative is dependent on the impact of scientific discoveries that do not yet exist in reality. Some games, such as those in the Half-Life series and Unreal series take place in a sci-fi universe that was created specifically for the purpose of the games. Others may take place in existing sci-fi universes, such as licensed Star Wars games. Common elements of sci-fi themed games include futuristic settings, high-tech items and weapons, and alien characters.

Project: Snowblind

Project: Snowblind is a FPS video game developed by Crystal Dynamics.
In a world similar to that from Deus Ex you play as Nathan Frost, a soldier with nano-technology augmentations.

Halo: Spartan Assault

Halo: Spartan Assault is the first mobile game in the Halo series. Progress and achievements are synced between Windows 8, Windows RT and Windows Phone 8.

Lost Planet 3

Lost Planet 3 is a third-person shooter video game developed by Spark Unlimited and published by Capcom for Microsoft Windows, PlayStation 3 and Xbox 360. The game is the prequel to Lost Planet: Extreme Condition and Lost Planet 2 and takes place on the same planet of E.D.N. III. The game will take a more story-driven narrative approach to the campaign similar to the first game.

Saints Row IV

Saints Row IV is an action-adventure video game set in an open world environment. It is developed by Volition, Inc. and published by Deep Silver. It was released for Microsoft Windows, PlayStation 3 and Xbox 360. It is the fourth installment in the Saints Row series, after the release of Saints Row: The Third in 2011. As in previous titles in the series, the player controls the leader of the Third Street Saints, who has now become the president of the United States.

Star Citizen

Star Citizen is an upcoming space trading and combat simulator video game for the PC Platform. Star Citizen will consist of two main elements: a persistent world massively multiplayer online game mixing elements of 1st person space combat and interstellar trade (known as Star Citizen) and a branching single-player and drop-in co-operative multiplayer campaign (known as Squadron 42), together with customizable private server components. (Source: Wikipedia)

Star Citizen is currently in development with an estimated release date in Q4 2014. Star Citizen is being entirely crowd funded.

Boson X

Quantum jump from planck to planck as you hit critical velocity in Boson X, a new rotational runner from Mu & Heyo. Build up speed inside a massive particle accelerator and generate high-energy collisions to discover strange new particles. Use precise timing and fast reflexes to navigate a subatomic world where floors and ceilings don't exist. Will you be fast enough to find the elusive Boson X?

Free to play. Visit developer website or Desura, or buy it on Steam for a few bucks.

Evochron Mercenary

Live the life of a mercenary or trader in an open-world space environment in the latest game in the Evochron series.

RiftSpace

Take on mercenary contracts, transport goods and explore freely in the first non-linear game from StarWraith 3D Games. It was followed by the Evochron games which build on similar open-world gameplay concepts.

Star Wraith IV: Reviction

The fourth and final game in the Star Wraith series introduces new features and more advanced multiplayer.