List of rational or transhumanist fiction and associated readings. Square brackets are word count, given when available.
Three Worlds Collide (Eliezer Yudkowsky) [24,990] First contact novella about ethics and game theory when meeting aliens with different values.
The Simple Truth (Yudkowsky) [6,325] An amusing, almost Monty Pythonesque, rationalist essay "to restore a naive view of truth."
Harry Potter and the Methods of Rationality (Yudkowsky) [650,000+] A rationalist fanfic where Harry was raised by loving parents who taught him Bayesian reasoning, and how he uses that knowledge to break the magical world. Introduces a lot of rationalist concepts while poking fun at Rowling's wizarding world.
Metropolitan Man (Alexander Wales) [80,000+] A rationalist, deconstruction fanfic of Superman. Features Lex Luthor as the villain protagonist as he comes to grips with the arrival of an alien god.
The Sword of Good (Yudkowsky again) [9,262] Trope destroying, D&D style fantasy, short story about the inequality of not using healing spells on peasants.
The Truth of Fact, the Truth of Feeling (Ted Chiang) [13,694] Almost a happy Black Mirror episode, it's two stories in one about the fallibility of human memory and how recording things affects us, whether it's by writing in a book or with an implanted eye camera.
Story of Your Life (Ted Chiang) [17,557] Novella about a peaceful first contact, and the challenges of communicating with an alien species. The film adaptation Arrival is quite good too.
Where Am I? (Daniel Dennett) [5,961] Short story delving into philosophical questions about personal identity when your brain is copied digitally and no longer in your body.
The Fable of the Dragon-Tyrant (Nick Bostrom) [4,886] Now animated on YouTube! But please read the post story notes in the original link Philosophical parable about death.
The Gentle Seduction (Marc Stiegler) [8,938] Short transhumanist story from the perspective of an average person with fear of drastic technology change.
17776 aka What Football Will Look Like in the Future (Jon Bois) A multimedia serial where sentient space probes watch humans who no longer age or die enjoying their unending lives.
20020 The sequel to 17776.
Utopia, LOL? (Jamie Wahls) [5,047] Transhumanist short story about a person waking up far in the post-singularity future, purposefully written with as many 2010s anachronisms as possible.
Manna (Marshall Brain) A short story about automation's two outcomes: capitalist dystopia or transhumanist paradise.
Pokemon: The Origin of Species (Damon Sasi) [~600,000+] Rationalist and gritty realism Pokemon universe where Pokemon counters are often lethal and legendaries are worse than natural disasters.
Ra (qntm) [~138,000] Serial ratfic where magic is a currently studied field of engineering, and functions as the next advancement after electricity. Received a secondary ending after many years.
SCP Antimemetics Division (qntm primarily) A sub-section of the SCP Foundation, this focuses on anti-memetics: things that censor themselves from the memory of others. SCP-055 and There Is No Antimemetics Division are the most recommended sections.