The Lost Valley

A very short and pretty walking simulator, with neither interaction nor story nor real exploration (it's quite linear). Essentially, it's a nice demo of CryEngine's photo-realistic lighting system. The choice of music is pleasant, too.

It can be a nice and relaxing way to spend 30 minutes. Just be clear on what you're getting in case you intend to buy this.

Also, warning: do not press the left mouse button during the game, because it will restart it! (I know, right?) Just use WASD and mouse movements.