I wanted to write about it, but I was sleep deprived and sleep depraved, after staying up all night to work on a project for work that I couldn't work on when other people were using the build system.
So. Cloud Ponies.
Penny told me about this in the first year we were married, 1981.
Some background on her family: Her mother left her father when Penny was eight years old, uprooting her from the school where Penny was well-liked and reasonably successful, and taking her and her two-or-three year old sister and her newly born baby brother and heading down to Redding, California. They moved into the basement of Penny's grandmother, her mother's adoptive parent (and the adoption was a HUGE secret, for no sane reason). The grandmother was a very nice grandmother for young, malleable, obedient girls, and having met her, I get the strong feeling that she was one of those 'withhold love, inflict guilt' types whenever someone disobeyed her.
Anyway. Uprooted, dragged to a far away place, losing her father (never got to see him again, apparently) and the kids at school had already formed their cliques and made their friendships. She didn't make friends there, for a long time.
In summers they took long driving trips. On the first of these, Penny was completely bored, forced to sit in the back seat of the air-conditioning-free car because Patty (the younger sister) would throw tantrums until she would vomit, and hence the phrase "Patty gets car-sick" was code for "Penny sits in back where she cannot see and all the cigarette smoke gets sucked into her face." Her grandfather and uncle would drive, primarily, and they drove a fixed distance every day, no stopping, no side trips, no actual sightseeing.
At some time on one of those trips, Penny (old enough to see out the window) noticed that there were small, transparent ponies running alongside the car, just where the car's shadow trailed along. They nibbled at the shadow, while running. They were actually full-sized horses, but something about the fact that they were not completely present meant that they were at the same time the size of a large-ish Saint Bernard dog.
One or two of the herd saw her, and there was some unspoken communication - that they were watching over her, to make sure that nothing horrid happened, and that they ate the dark from clouds and sometimes from shadows, leaving behind light and color.
Later, when she returned home, she saw the herds in the sunsets, and sometimes one or two would come to visit her when her mother was losing her temper (a too-common experience) or her grandmother was being particularly arch, imperious, and arbitrary (also a too-common experience.) I never thought about why they visited her then, and she never talked about why it happened, but I think they were eating the darkness from her life, leaving behind color and beauty.
She told me very seriously that the ponies were extremely serious about the importance of their job, and that being talked about too much, or noticed too much, would annoy the stallions and they would move the herds away for a while.
So we didn't talk to them, or unduly notice them, except at a particularly gorgeous sunset.