Nethack

Ah nethack.

So friggin difficuilt I can't stand it.

So friggin engrossing I... can't stand it.

An example of a phrase commonly heard in the nethack forums...
"THEY THINK OF EVERYTHING!!!"

Eat a floating eye corpse and you'll get ESP, which will allow you to see enemies anywhere on the map, but only while blinded. To take advantage of it, you may want to drink a potion of blindness, or preferably, find and wear a blindfold. Of course, while blindfolded, even with ESP you won't be able to see inanimate objects on the floor -- when you find piles of items, your character will have to "feel" for them. Oh, and you won't be able to read scrolls. Whoops! In that pile of items you just felt is a cockatrice corpse -- fortunately you were wearing gloves, otherwise you would've been turned to stone just by touching it. But now, blind and protected, you can pick up the cockatrice corpse and use it to attack monsters -- now your enemies will turn to stone when you strike them! Unfortunately, their inventory turns to stone as well. Hey, no problem -- you've got a pick-axe, so you can chisel open their statues to yield a pile of rocks and any of their old possessions. Sadly, thanks to the blindfold, you can't see a nearby pit and tumble inside. Too bad you were holding the cockatrice corpse -- it landed on top of you and turned you to stone. Yet Another Stupid Death, and another reason to cry out in anguish because they think of everything!

Nethack has a HUGE following, because it focuses on the aspects of gameplay as opposed to the aspects of flashy graphics, and scantily clad females...

This name has earned the nickname "The Gradewrecker" because, once you get started, you can kiss that GPA goodbye...

If you're interested in nethack, by all means, play it. And by all means, read anything you can about it (not including spoilers of course) the gameplay is very difficuilt, you get one life. You can suspend your game (leave and come back later) but not save. You must play this game with all of your brain... or you'll find yourself getting frustrated and tired of such a graphically-impaired game.

Don't take my word for it... find our for yourself...