A certain culture believes that evil can live beyond the grave. They also believe that the destruction of the dead body can keep that one from coming back. Destroying the newly deceased body can destroy the soul if done properly. They first burn the body for 24 hours, smash the remains as well as possible, then burn the what is left for another 24 hours.
An ancient, psuedo-immortal race has been manipulating something important (politics, religion, economics, etc.) for centuries. Hardly anyone is aware of them, let alone their goals.
One of the most wanted assassins in the realm looks exactly like an important person (local nobility, PC, etc.) This may or may not be common knowledge.
Thieve's House or thier main front: All the floors are designed to squeak when stepped upon or to sag or bend sending a small shake along the beam, somewhat like a spiders web, to alert those inside.
There are two major (read feuding) provinces in the kingdom. The Lord of one is secretly a mad, power-hungry despot, constantly plotting against the king. The Lady of the other is secretly an ancient silver dragon.
In addition to the Thieves' Guilds, there is a hierarchy that all thieves are part of. Rank is based on skill, and can be raised or lowered at any time. The Queen of Thieves, the greatest living thief in the world, is the ruler. Guildmasters answer only to her, and she answers to no one at all.
The ochre sands stretch for miles around. Something kicks up the dust. It's a yak. A desert-yak. It ambles slowly, nuzzling the ground for the low-growing shrubs. The ranger freezes. "Stay very still," he warns. "Don't move at all."
"What is it?" you ask, breathlessly.
"It's the most dangerous creature in the whole Ocadian desert. And it's about to eat that yak..."
The city of Nausopol is built on stilts. Lots of very sturdy stilts and butresses, of course, because it rises about five hundred feet from the ocean. Even the most terrific of storms is only heard in the city as a distant cacophony of blasts as waves strike the solid stonework fathoms below. It has never been attacked because of its isolation and impregnability.
It's not a place for the faint-hearted: vertigo and sea-sickness are not desirable traits. But when you are standing in the middle of the city there is no way you could tell that you were standing above an ocean, separated only by a gulf of air and a few stones.
A thousand steps lead down from Nausopol to the floating docks. These docks are pitch-coated wooden and can be raised by winches during squalls. Trade with other cities and countries is good: Nausopol is built over a sunken atoll whose minerals are still mined by divers, and it was from this that it originally derived its wealth.
But the principal method of getting to and from the city is by riding the giant sea-eagles which have been captured and bred for that very reason.
The cliff-hunters ride sheer-stalkers vertically down the cliff faces to reach the nests of birds and steal their eggs for sport. Sheer-stalkers are vicious agile lizards about the size of large komodo dragons. They must be muzzled and harnessed, but even so there have been some nasty incidents...
The village sits on the edge of the deep fjord, often engulfed in mist or rain. Its people are fishermen, who work even through the sea-ravaging winter. And they pray to the gods of the deep.
At the beginning of every winter they hold a summoning ceremony. Three boats are taken out into the fjord, a hornsman on each. The mournful horns are blown in the language of the whales, the gods of the deep. The whales sometimes appear in answer to these calls, and it is taken as a good omen when they do.
To a party of PCs wandering the misty hills and valleys nearby however, the doleful whalesong of the horns can be disturbing and misinterpreted...
Diseased people, (leprosy or any other such fear inducing disease) when traveling, will often times wear a cloak that entirely covers their body and ring a bell as they travel, used as a warning for any others to stay away. Could be used for a disguise or safe passage.
A large vertical cave has a constant, strong wind blowing out of it from the bowels of the earth. If one was to jump into the currents they would have a controlled ascent on the winds till they reached a height where their weight and the winds force reached equilibrium. Impossible to climb down naturally. What is it? Natural winds from the earth or a complex magical protection for an underground lair?
With regard to the plot "Sleeping Mines of Elathon":
You manage to get the water wheel in the mine working which operates a pump to clear the flooded lower levels. As you explore the dank tunnels of the lower galleries, you can hear the creaking of the wheel above. You enter a low-ceilinged passage and are crawling on your backs, when the creaking stops. The water starts seeping wetly around the back of your head...
Finally got the idea for an orcish currency:
A cold-hammered piece of raw iron, resembling some kind of a dagger. The Dagger is easy to carry, hard to forge, may be used as a crude weapon in case of emergency AND the iron being a valuable resource... may be used directly for weapon-making. May be carried openly on the belt of a mighty Orc. A new insult: 'to beat someone with someones money' . Self-explanatory.
Mining in a certain area turns all exposed skin (maybe just parts that are actively disturbing the chemicals that cause the reaction) of the those doing the mining to a dark blue color. Will wear off taking as many years/days spent in the mine.
Custom among pirates to yearly vote for their leader. If a majority believed the leader was doing poorly they could hold another vote. Democratic except in times of battle and danger at sea. Could bleed that over to some 'honorable' bandits.
A comet flies through the sky every so many years. During this time no fire is able to be lit anywhere the comet is visible.
The Black Forest- actually a part of another forest, is said to be cursed by the presence of some horrific monster, which burns the very earth with its body!
No one has yet seen it and lived to tell, so be warned!(see NPC Aurelius Blackfoot for details)
Sword sharpness is equal to the status and skill of its wielder.
A people who believe it is incredibly impolite to speak to anybody they meet for the first time. They believe their actions should speak for them until they are comfortable in each others presence and can then trust each other. Only then would converstation be appropriate.
What to export or import....
Fabric: wool, linnen, silk...
Wood: raw-material, furniture
Metals: iron, gold, silver, copper...
Wine, beer, mead, spirits...
Animals: horses, sheep, swine, cows...
Coloring-powder (for fabric, ink...)
Raw-material to make fabric: unprocessed wool, linnen, silk...
Glass: Windows, figurines, glasses, raw-material...
Tea (not sure about my spelling here, but I mean the hot drink Englishmen drink instead of coffee!)