These short stories are all under 2,000 words, as far as I know. For an excellent anthology, check out 75 Short Masterpieces. (Amazon) See also:
Short Short Stories
“Sunday in the Park” by Bel Kaufman
Morton and his wife sit on a park bench while their young son, Larry, plays in the sandbox with another boy. Everyone is contented and happy until the boy suddenly throws a shovel full of sand at Larry. (Summary & Theme)
“Old Man at the Bridge” by Ernest Hemingway
During the Spanish Civil War, an old man sits on the roadside, exhausted and discouraged. Everyone is fleeing from the advancing Fascist army.
This is the fourth story in the preview of The Complete Short Stories of Ernest Hemingway. (92% in)
“The School” by Donald Barthelme
A teacher relates all of the experiences with death that his class has in a single school year.
This is the second story in the preview of The Scribner Anthology of Contemporary Short Fiction. (41% in)
“Sredni Vashtar” by Saki
A sickly, ten-year-old boy, Conradin, seeks refuge from his cousin and guardian by playing in a tool shed. He has two pets there, a hen and a ferret. He imagines the ferret is a god.
“Sredni Vashtar” can be read in the preview of The Weird: A Compendium of Strange and Dark Stories. (54% in)
“In a Tub” by Amy Hempel
When a woman feels her heart has stopped, she heads for a church.
This story can be read in the preview of The Collected Stories of Amy Hempel. (38% in) There are a few other short selections in the preview.
“Ripe Figs” by Kate Chopin
A girl wants to visit her cousins but her Godmother says she has to wait until the figs are ripe. (Summary)
Read “Ripe Figs”
“Story” by Lydia Davis
A woman gets a message from her boyfriend. He’s busy and won’t be coming over, but he’ll call later. She waits for a while, then goes to his place.
This story can be read in the preview of The Collected Stories of Lydia Davis. (15% in) There are a few other very short stories available in the preview.
“Girl” by Jamaica Kincaid
In this prose/poem hybrid, a mother gives her daughter some advice about how to behave, and on becoming a woman. (Summary and analysis of story)
“Girl” is the sixth story in the Amazon preview of The Penguin Book of the Modern American Short Story. (92% in, select in TOC)
“Bowery Station, 3:15 A.M.” by Warren Moore
A man descends into Bowery Station. He sees a girl standing alone on the Brooklyn-bound side of the platform. Her lips are moving and she’s tense; he can tell what she’s getting ready to do. The Brooklyn train approaches.
This story can be read in the preview of Dark City Lights: New York Stories. (78% in)
“Buck Hunt” by Livia Hunt
Lilly is at a bachelorette party with her friends. She was also talked into letting her cousin Madison come, despite the recent unpleasantness. Her maid-of-honor, Fiona, has arranged a special game—a Bachelorette Buck Hunt.
This story can be read in the preview of Stories on the Go: 101 Very Short Stories by 101 Authors. (64% in)
“Flashlight” by Griffin Carmichael
There’s a lot of screaming during a blackout, even though the lights have only been out a few minutes. A woman looks for a flashlight so she can see what’s going on.
This story can also be read in the above preview of Stories on the Go: 101 . . . (73% in)
“#8” by Jack Ritchie
A man and his young redheaded passenger listen to a news report about someone who’s killed seven people. The police are searching the area and have roadblocks set up. The young passenger is impressed with the killer, and talks about his motivation and how smart he is.
This story can be read in the preview of Alfred Hitchcock’s Mystery Magazine Presents Fifty Years of Crime and Suspense. (65% in)
“‘Taking Mother Out'” by Elizabeth Taylor
Mrs. Crouch is eighty-years-old but seems younger, and she likes to draw attention to her age. Her son, Roy, is flashy and cynical and seems to know everything. An elderly bird-watcher bores the company with his sightings.
This story can be read in the preview of Complete Short Stories. (92% in)
“A Haunted House” by Virginia Woolf
All through the night, there are doors shutting and a ghostly couple walks hand in hand through the house, looking for something. If the couple living there get up to look, the house will be empty.
This story can be read in the preview of The Complete Works. (71% in, or select Monday or Tuesday in TOC)
“The Story of an Hour” by Kate Chopin
A woman receives the news that her husband has been killed in a train accident. She processes the news over the next hour, experiencing a range of emotions.
“Miss Brill” by Katherine Mansfield
A middle-aged woman takes a weekly Sunday walk. She likes to observe and listen to people, but she overhears something that upsets her.
“One of These Days” by Gabriel Garcia Marquez
A corrupt mayor needs treatment for an abscessed tooth. He goes to an unlicensed dentist. The dentist doesn’t want to help, and they exchange some words. (Summary & Analysis)
“She Unnames Them” by Ursula K. Le Guin
Someone has been persuading all the animals to give up their names. Most accept it without much resistance. It makes them feel closer. (Summary & Analysis)
“Say Yes” by Tobias Wolff
While doing the dishes together, a husband and wife start discussing interracial marriage. The wife thinks it is fine, but the husband believes the cultural differences would be insurmountable. (Summary & Analysis)
“Condensed Milk” by Varlam Shalamov
The narrator is in a Russian labor camp working in a mine. He envies Shestakov, an engineer-geologist who works in the office. While longing for some bread, the narrator is approached by Shestakov. They walk behind the barracks to talk. Shestakov has an escape plan. (Summary & Analysis)
Read “Condensed Milk”
“The Egg” by Andy Weir
You’re killed in a car accident on your way home. You’re concerned about the family you’re leaving behind, which the narrator tells you is what he likes to see. It turns out you’re going to be reincarnated. (Summary & Analysis)
The first section of Margaret Atwood‘s collection Murder in the Dark is made up of very short stories. The following 4 can be read in the Amazon Kindle preview.
“Autobiography”
The narrator relates the first thing she remembers—where the lake meets the sky. On the right were a river, a dam, a covered bridge, some houses, a white church and a small rock island.
“Making Poison”
The narrator remembers making poison with her brother when she was five. In a paint can, they put all the poisonous things they could think of and acquire. They stored it under a neighbor’s house.
“The Boys’ Own Annual, 1911”
The narrator finds an old periodical in her grandfather’s attic. The issue containing the final instalment of an adventure story is missing. It never came.
“Before the War”
Before the war things were different. You could fish and shoot bears. Logging is different now too, with trucks and bulldozers.