My game du jour is Brogue. Brogue is a Roguelike, or "a game like Rogue". Rogue was one of the early offshoots of the Adventure genre; a graphical adventure game back when drawing with text was an advanced technique. In Rogue, your character was an @, all the objects on the ground were symbols, monsters were lower and upper case letters, and the things that happened were all described in a text sidebar.
The hallmarks of a Roguelike are randomly designed (or partially randomly designed) dungeons, items and equipment with hidden properties that have to be tested or used blindly (like potions that are described by color, at least until you drink it and find out what it does), and tough monsters that often have to be defeated by clever item use. Roguelikes often use the limited graphics they are known for as a starting point to make extensively complex and complicated environments. Roguelikes are also known for being dense and esoteric.
So what is Brogue? Brogue is an attempt at an accessible Roguelike that still uses ASCII* text graphics. Monsters are still single text characters, but you can hover over them with your mouse to get all the information on it, including its powers and how difficult it might be to fight. In fact, you can control the entire game (including inventory commands) with your mouse. Items start unidentified, but you can access a chart of all the items in the game, and which ones you've already discovered. Each level fits on one screen, so you can see the big picture. Best yet, the text is in full color, including shadows and lighting effects like luminescent phosporous and fire.
Anyway,
try Brogue.
*It's probably unicode text, actually, but you know what I mean.