HAREIDLANDET is yet another fractured ruin of a once-prosperous world.  The original Hareids were so wealthy that each family lived in a domed castle with its own artificial sun and stars.  Their ersatz firmaments operated on schedules that were completely divorced from the actual rotation of the planet.  It was therefore a sign of higher status to insist that one's own day-night cycle was the proper one, and visitors must not come calling in the middle of the "night".  When company was permitted, it was considered obligatory to ostentatiously dispose of "outdated" valuable objects into the same outdoor refuse pit that was used for the disposal of sewage.  Whether this custom had anything do to with Old Hareidlandet's downfall is unknown, but the current inhabitants still sell their scavenged relics.

MADEC is a desert world which is occasionally subject to torrential downpours at any random location.  Madeccans carefully watch the skies and consult their various oracles to divine the direction of the next deluge, with varying levels of success.  When the rains do come, they spur the growth of Madec's largest native plant, the tollendal tree.  Tollendals rapidly absorb as much of the moisture as possible, and are capable of increasing in height by as much as 10 paces a day.  In addition to providing the majority of the planet's food, tollendals serve an important symbolic purpose to Madeccan society.  Whoever can climb the tallest-growing tollendal is acclaimed as monarch of all they survey.  The privileges of that position are to a large extent honorary, but chief among them is the high-climber's desirability as a mating partner.  This is to be enjoyed while it lasts, because once the nearby water has all been consumed, tollendals inevitably collapse and die.  Madeccans preserve the vegetable matter as best they can, and wait for the next rainfall to bring them, perhaps, a new ruler.

THEOPHANES is by far the most habitable of the satellites of the gas giant Mytilene.  It has a breathable atmosphere, large freshwater lakes, and adequate agricultural potential.  Because it is enveloped by the ring system  and numerous other moonlets of Mytilene, it is frequently subjected to dangerous meteor strikes.  Theophanes' ruling oligarchy lives in a well-shielded fortress that protects them from harm, but the rest of the population is not so fortunate.  To encourage their continued economic support, each year one worker is selected to bring their entire extended family inside the fortress and become a new part of the permanent elite.  Each unit of taxes paid corresponds with one entry into the lottery which determines the lucky winner.  Friends who remain outside may receive an occasional gift basket, but on the whole they report that their former acquaintances swiftly lose interest in associating with them or even writing letters.  Nevertheless, support for the government remains high, as does hope for living in the Fort next year.

PALANCA has widely-scattered settlements occupying the arable regions of the planet, which are separated by mildly toxic wasteland.  Each settlement supports exactly one church, that of the Homeless Carpenter.  Said profession is solemnly revered by Palancans, who strive to outdo one another in feeding and clothing any stranger who offers to perform that sort of work.  Anyone whose previous employment has failed need only learn the bare rudiments of woodworking before making the arduous journey to a neighboring village, where they will of course be a stranger.

MARMOL is widely known as the "planet of corrupt rich fools".  One certainly needs to be rich to live there, as expensive protective equipment is needed to survive the frequent electrical discharges between Marmol and its natural satellites.  Being corrupt is not a requirement, but there are plenty of other places for rich people to live without being corrupt; indeed there are others where being corrupt is not a significant problem.  But if one isn't already foolish before emigrating to Marmol, it doesn't take long before that appelation becomes appropriate.  The addictive spice called "älluis" comes from a native plant's pollen, and even casual exposure usually leads to increased consumption.  The most damaging effect of älluis dependency is a progressive decrease in intelligence.  Inhabitants don't need to take stupid risks to get more älluis, since it is easily acquired, but eventually they always do.  One too many unshielded walks to get another sniff results in an almost complete reduction to ash.  Little research has been done to determine why Marmol has any inhabitants at all, since the rest of the galaxy is just as happy to be rid of them.

WINDY is a planet in the Terris sector with the surprisingly uncommon trait of being named after one of its physical features.  A vast and permanent cyclone circles this world, with sustained winds sufficient to sweep an unprotected person off their feet.  Protection against this danger is provided by sturdily-constructed contiguous buildings which form an interconnected megalopolis.  Transport ships are occasionally able to land at one or the other side of this city as dictated by the position of the storm, and an internal tram system conducts people and goods with admirable efficiency.  Windies can and often do spend their entire lives without leaving the great city of their home.  There is just one complication caused by their culture, and that is the practice of wind dueling.  If any person feels that they have been insulted or mistreated by another, they may insist that both parties "step outside".  This may involve a lengthy journey to actually reach an external door nearest to the hurricane, and perhaps an apology or payment will settle the matter before exiting becomes necessary.  If it does, however, the duelists are not permitted to attack or even touch each other.  They may only jockey for position while attempting to remain standing, and perhaps shout their demands over the raging winds.  Fatalities are rare, but visitors are strongly cautioned to remain polite and not tempt the locals to engage in this custom.  It is certainly not a fun and safe activity as sometimes advertised by disreputable touts.

MARCOLI is one of the most paradisical planets known to exist, at least from a climatological perspective.  Warm seas and gentle breezes predominate.  Each of the planet's numerous lush islands is home to a population which is fanatically devoted to one of the many native plant species.  No Marcoline can eat any other food or wear clothing woven from any other material.  How they decided to specialize in such a strict fashion is a mystery, but apparently it works well enough, because all of the inhabitants remain healthy and adequately clothed.  One might expect each island to cultivate only its chosen fruit or vegetable, but that is unfortunately not the case.  Windblown spores germinate everywhere in the rich soil of Marcoli, and the plants seem quite intent on growing entangled with one another.  So growing their crops is not difficult for the Marcolines, but harvesting them is rather labor-intensive.
Worldwide friendly trade ensures that each agricultural product eventually reaches the island where it is most appreciated.  Visitors are advised to carefully research the islands they intend to visit, and attire themselves appropriately using exported goods available throughout the Sunderland sector.  Imported food and clothing is strictly prohibited.

OSORIO is inhabited by capitalists who are exceptionally committed to rapid turnover.  A single day is considered to be the maximum lifespan of any retail business venture.  Every morning, new signage appears on every storefront, advertising an entirely new line of products and services.  Of course, competition is intense to stake out a claim on the most popular business sectors.  One has to get up pretty early to be the day's most popular sign manufacturer, for example.  But if inspiration, dedication, and other corporate imperatives fail, there is always substantial demand for garbage collection and recycling.

CADDO is an icy moon of Bole which is occupied by a militaristic sect of that planet's Hakuraku society.  They emigrated to avoid the necessity of living almost entirely in protective darkness, but they are sworn to protect their brethren and the brightly-glowing orb that dominates their night sky.  Fortunately there have been no overt threats to Bole, although whether this is due to their protection or otherwise has not been demonstrated.  Their most remarkable achievement is the development of a chemical matrix called "yaoshu" which allegedly imparts knowledge directly into a person's brain after it has been absorbed through the skin during a ritual "Spirit Dance".  The yaoshu chemicals are said to be carefully "programmed" with whatever skills and memories are needed for a person's role in the society.  One constant among all those patterns is a keen and constant desire to remain on Caddo and serve the Hakuraku faithfully.  At least this is the observed behavior of all whose curiosity has compelled them to take an oath before taking a yaoshu treatment.  Perhaps they are being compelled by threat of force rather than a force of will, but no one has ever abandoned Caddo.

A user has asked if I would consider adding direct messaging to OPW. Hmm.

I can think of one constraint on that feature right away: the bar to establish your right to DM someone needs to be pretty high. Like maybe you have to be mutual followers to start with, and then you can request DM access from that person. Even then I'm not sure how I feel about it. It's certainly not posting once a day. But it has a lot of important applications in situations that call for compassion, rather than being a stickler for the "spirit of things." Hmm.

Private comments to specific responders on a particular post have also been mentioned as an idea. Perhaps you, as the original poster, would be able to reply to a commenter privately.

That  stays closer to the idiom of One Post Wonder, but I think that it could generate confusion, e.g. accidental references to things said in private comments in public comments on the same post.

What do you think?