Proper

HUD is proper in widescreen.

Need for Speed Rivals

Two factions, one big map: Rivals combines the dual career mode and high-speed freeway chases of 2010's Hot Pursuit with the openness and upgradeability of 2012's Most Wanted. New features include dynamic weather and optional MMO-like connectivity.

The Stanley Parable

The Stanley Parable is a first person exploration game. You will play as Stanley, and you will not play as Stanley. You will follow a story, you will not follow a story. You will have a choice, you will have no choice. The game will end, the game will never end. Contradiction follows contradiction, the rules of how games should work are broken, then broken again. This world was not made for you to understand.

Trainz Simulator 12

Trainz Simulator 12 is a 3D railroad simulator that uses DirectX or OpenGL with multiplayer and the option of downloading 3rd party tracks, railcars, and objects.

Jazzpunk

Jazzpunk is a comedy adventure set in an alternate reality Cold War World, plagued with corporate espionage, CyberCrime, and sentient martinis. Gameplay is inspired by spoof comedy films and cartoons of yesteryear, with a focus on weird gadgets, exotic locales, and open-world style exploration.
(source: steam store page)

Marathon

Defend the titular colony ship from alien boarding parties in the first game in Bungie's Marathon trilogy.

Rescue: Everyday Heroes

Do you have nerves of steel and a calm head in times of danger? Then you can join one of the most respected careers in the world in Rescue 2013 Everyday Heroes, from Excalibur’s emergency services PC game range. Rescue 2013 Everyday Heroes is the first fire-fighting simulation for PC & Mac to include genuine British fire engines and ambulances as well as their continental counterparts.

In this fire-fighting simulation game you’ll be rescuing people trapped in car crashes, dousing the flames of burning buildings and even providing emergency medical care to the injured.

Spelunky

Upgraded and expanded remake of the popular freeware game from 2009.

Spelunky Classic

Explore mysterious caverns to collect treasures while avoiding traps and monsters.

Spelunky is a freeware game first released in 2009; it was renamed to Spelunky Classic following the release of an enhanced commercial version in 2013.

Unepic

Embark on a strange adventure in a vast castle with gameplay inspired by the Castlevania series.

Mark of the Ninja

In Mark of the Ninja, you'll know what it is to truly be a ninja. You must be silent, agile and clever to outwit your opponents in a world of gorgeous scenery and flowing animation. Marked with cursed tattoos giving you heightened senses, every situation presents you with options.
(source: steam store page)