Speaking of the Immanence Design (the actual play I've mentioned earlier), I've found my favorite part in the whole thing, a story (well, children's tale) within the setting. It just oozes atmosphere and is quite educational.
Once there was a man who was very good at hiding.
This was a very long time ago, when there were very many people who were very good at lots of things. There were people who were very good at fighting and people who were very good at leading and people who were very good at talking and people who were very good at knowing. There were even others who were very good at hiding, but this man was the best at hiding of them all. He was called the Fade, but that wasn't really his name, and nobody actually called him that way back then.
There were also lots of people who were less good at things than the people who were very good at them. One day they got jealous, and decided to get rid of all the people who were better at things than they were. So they all got together and killed as many as they could find, the ones who were very good at fighting and the ones who were very good at leading and the ones who were very good at talking and the ones who were very good at knowing, but certainly didn't know that this was going to happen, and even some of the ones who were very good at hiding, who apparently weren't as very good as they'd thought.
But they couldn't catch the Fade. Not at first. But after he'd escaped, he looked around at the world, and saw that he was one of the only ones left. He wouldn't be able to hide forever, not after all his brothers got found and killed and everybody was looking out for just him. But the Fade was clever, and he thought that if he couldn't hide himself, he could hide all the parts that made him himself.
First he hid his name; he dug a hole, then he put his name in it, and when one of the Fair Folk came along to see what was caught in the hole, the Fade pushed him in. After a week without sustenance, the Fair One ate the name so that he wouldn't starve, and then the Fade let him back out, so that he could return to the Far Marches of the Wyld and take his name with him.
Next the Fade hid his memories. He put them all in little boxes, and made little straps so that he could hold onto them all at once. That way his memories didn't have to be in his head, and when he wore the little boxes, he'd know everything he'd need to know.
His two swords were bright and made of gold, so he had to sit and think for a month about where to hide them so that they wouldn't glitter and shine and draw attention to themselves. He sat and sat, until finally one day he had an idea. He got up and he walked as far north as he could (and this was very far indeed, because Creation was much bigger in those days). He swam through seas choked with ice, but the cold couldn't find him to suck the life out of him. He walked through miles and miles of lifeless tundra, but hunger couldn't find him to sap the muscle off his bones. He climbed ice-cliffs as tall as the sky, and the earth couldn't find him, so that even when he slipped off, he wouldn't hit the ground but could instead just go back to climbing again. Finally he made it to the very end of Creation, and he grabbed the edge and he looked over the side. He couldn't see what was beyond -- he was very very good at hiding, but he was still mortal, after all -- but he could see that, just as he thought, there was a seam between Creation and the Underworld, like the space between two slices of bread. He slipped his gold swords into that seam, and so long as they stayed in-between, nobody could guess where they were.
Then the Fade walked back south, and as he did, he thought some more. Some of the people who were trying to kill him could read things in the sky. Worse, they were going to get to him sometime or other, and even if he did manage to hide from them, he couldn't hide from Time. Once he died, they'd have their hands on him, and it would be the end. All his hard work would be for nothing. He thought and he thought, but he couldn't see any way out of it. The more he thought, the more desperate his plans became -- impersonate one of the Maidens! Learn to walk on his cheekbones, so that when Death came, he'd laugh so hard he'd let the Fade get away! Suddenly the Fade felt very alone. His memories were all hidden in far away boxes, his weapons were far out of reach, a Fae noble had stolen his name, and most everything in Creation wanted to kill him. The Fade couldn't hide himself from despair, and he sat down on top of a glacier and began crying with all his might.
He didn't know how long he'd been weeping when the voice interrupted him. "Pardon me, O Prince of the Earth, but I cannot help but notice that you are in some distress." The Fade looked up. Standing in front of him, on top of the glacier, was a man wrapped crown-to-toe in a beautiful cloak. The man had one big extra eye instead of a mouth, and when it blinked, the Fade heard his words melt their way up through his nostrils. "Do not be confused, O Prince, for I am one of the Yozis, and the Gods, in their jealousy, decreed that we must be all mixed-up before they would allow us to live. Now I see that their jealousy has spread so far that they cannot even suffer their Chosen to live in glory, for why else would a man hide his name, his memories, and his swords, if not to try to hide himself from the Gods?"
"You speak well, O Demon Prince," said the Fade, his cleverness returning now that he saw a worthy foil. "Indeed, you have the right of it, and I am to be cast down like the rest of my brethren, because we grew too bright and too strong for our lessers to abide. But tell me, foul one, how is it that you can be here in Creation, under the watchful eye of the Unconquered Sun, treading upon the flesh of your traitorous sister, without bearing the dismaying brunt of their disapproval?"
"Ah, the pitiful remnants of my soul are cut to the quick by your plight, O Prince, so I will honor your question with a reply, though it is one of the darkest secrets of my green-lit home. The virtue is in my cloak," the demon said, flaring the garment wide to allow the Fade to see the inner lining. "Witness the yellow-green constellations of my home, coaxed down from the squat heavens of Malfeas by the seductive songs of the tower-sirens which dot my brother's thick surface-skin, and sewn into the trim by generations of seamstresses, each of whom could manage only a single stitch before being immolated by the citrine radiance. While I wear it, none who dwell under the stars of Heaven can know me, or my fate."
That cloak is a cunning thing indeed, thought the Fade. Fortunately, I am the more cunning still. "O Yozi," he said out loud, "it is clear to us both that your garment is the solution to my current predicament. Still, it would be insulting to us both to presume that you could be cajoled into simply giving it to me." The man blinked his great mouth-eye in pleasant acknowledgment, for the Fade's words were no less than his due. "But it would demean neither of us to consider a trade, would you not agree?"
"Indeed, O man," the Yozi twinkled, "you know that it is in the nature of demons to appreciate a finely-crafted bargain. And yet, do not think me disrespectful were I to point out that you have very little with which to bargain. You are bereft of name, memory, and weapon: what could you offer in exchange for this wondrous cloak, the hell-borne fruit of ages of labor?"
"I could offer you my soul," said the Fade.
"Wouldn't give an obol for it," confessed the Yozi, mirth gleaming through his eye. "That's always the first thing you mortals offer, and there's rather a glut on them, I do confess."
"I had anticipated that, and made the offer for form's sake, merely. Might I then offer you my mouth?"
"With which to speak, perhaps? I can do so very well already, as you no doubt have observed. With which to lick the secret places of my consort Brasidas, the Wasp Whose Sting Is Inspiration And Abandon? The novelty would wear out long before your tongue, under the acid touch of her blissful secretions. To affix to my forehead, and therefore cause the mortals to scream even louder when I ride out among them during the five days of Calibration? You must think me a crude, rough beast indeed to propose such a thing."
The Yozi, bored, began to turn away, when the Fade's voice came yet again: "Truly, sir, yours is a discerning mind, and a keen eye for a bargain, if you will allow so clumsy a pun to pass my lips without taking your just due of umbrage. I tender to you, then, my final offer. For your cloak, sewn with the yellow-green stars of Malfeas, I make this offer: I will give you my death."
The demon stood teary-eyed in amazement. "Your death? What would I want with your death? It is a limit, the boundary which circumscribes you, mortal. What use could I, undying, have for such a thing?"
"Ah," said the Fade, studiously diffident. "I had thought better of the fabled perversity of the Demon Princes. They sought out all that was forbidden, to embrace them for the sheer joy of violation. That they might understand the breathtaking vertigo of limit, of constraint, of boundary. That they might thrill in tainting their own natures with the base stuff of mortality. Alas, I was misinformed, and I therefore am undone." Dejected, the Fade began his long slow climb back towards the frozen seas, and the new Realm of the Dragon-Blooded which wished for nothing better than his heart.
"Wait!" called the Yozi. "You have piqued my interest, O Prince of the Earth. It is true, none among my fellows have tasted this death of yours -- at least, none who dwell now in Malfeas, death being the part of our Neverborn cousins who slumber dreamingly on Oblivion's blasted slope. Such a thing might have value indeed, value enough to be parted from my cloak."
"I salute your discernment, O demon, and gratefully accept your acceptance. As there is no use wasting time in matters of business, I trust you will have no objection to handing over the cloak immediately?"
"Fine, fine," the Demon Prince said grouchily, unhappy to be giving up his prize before first tasting the sweet merit of his bargain, and divested himself of his great cloak. The Fade wrapped it around himself hungrily, savoring the scent of mothballs and burning metals. "Now, then, the cloak is yours. Where, then, is your death?"
"It is here," boomed the earth, as it felt the foulness walking on top of it. "It is here," whispered the sky, as its gaze beat down upon the uncleanness which offended its sight. "It is here," sighed the wind, as it caressed the demon like a hated lover. "It is here," cried the host of Sidereals, who had been sneaking up on the Fade even as he bargained.
And that is how the demon got his death, and the Fade got his cloak.