Alone

In the near future, you are a survivor of the plague. And you have just run out of gas. Fortunately there's a gas station nearby...

Alone takes place on a very compact map. A good handful of locations are accessible. After finding a hidden entrance, the game more than doubles in size, but it retains a closed and claustrophobic feel. This, and the fact that the protagonist is entirely alone make the world seem very small and threatening.

The puzzles are almost all of the lock&key variety. But it goes out of its way to show how much variety there still is in the "simple" lock&key category. Electronic doors open from a distance, opening one door closes another,... The key to one door is even too heavy to handle and must be moved mechanically.
All these are completely logical, but it may take some tinkering to understand the relations between the parts.
I absolutely loved the final puzzle. It is possible to settle for a simpler solution and still get your initial objective (fuel). However, if you are willing to think a few more logical steps further, there is a much more rewarding ending to be found.

The sense of achievement in this harder solution lies mostly in seeing some real character development in the protagonist. It's described in few words, but it is real and touching.

The writing is crisp and clear. Rooms are easily visualized to give a good view of the important bits. With the exception of one small component, it's not about finding the bits by looking under the rug, but about how the bits interact (sometimes from far away). The longer ending paragraphs are a great reward after the concentrated focus on the puzzles.

A very good game. It could have used a bit more dry humor (sorry, in-joke...)

Recommended wholeheartedly!