A Dark Room is a text and ASCII based game, played via web browser. The game is not what it seems to be at first, so reading further will expose spoilers. The game starts as what seems to be a minimalist story: you are in a dark room, and you must stoke a fire. After doing this for a while, someone else shows up: the builder. You gather more wood to keep the fire going, and then the builder suggests you build a cart to carry more wood, and some traps to catch meat...
From there, the game quickly becomes an exploration and resource gathering/management game, somewhat akin to if a Civilization or Masters of Orion type game were designed with only ASCII graphics. The exploration also has some similarities to a Roguelike game. Despite the minimal graphics and terse nature of the descriptions, the game actually has a plot, and one with quite a few plot twists. The first time I was shown this game, I spent seven hours playing it, despite the total lack of what many would consider a "gaming experience".
One of the biggest appeals of computer games for me is always the curiosity of seeing what was around the next corner. In modern games, this is usually translated by having such novelties as a 10 minute long cutscene with cgi characters, voice actors and a soundtrack. What is so interesting about "A Dark Room" is that (for me, at least), it communicates the same interest with the absolute minimum. The game map is made out of ASCII characters, and the first time I encountered a Capital "S", it had the same compulsion to find out what plot twist this could mean as a cutscene could for a modern gamer.
The game can be played here:
http://adarkroom.doublespeakgames.com/