Ask HN: What's the most creative 'useless' program you've ever written?

Hacker News Discussion ↗

Overall theme: “Useless” as core hacker practice

  • Thread is a long show-and-tell of playful, non‑practical projects.
  • Many argue this kind of tinkering is central to “hacking”: exploring ideas, constraints, and tools for their own sake.
  • Several note that ostensibly useless projects later gained real utility.

Visual, artistic, and generative projects

  • Numerous graphic toys: Mondrian/Piet‑style image generators, fractals and Mandelbrot zoomers (including touch‑zoom), particle/fluid simulations, kaleidoscopes, ray tracers, 3D ASCII cubes, and vector/pen‑plot art engines.
  • Many personal sites use interactive art (villages, perlin‑noise backgrounds, particle fields, animated ASCII, clocks that encode time as colors or digits).
  • Projects map images into other media: SVG primitives, Excel cell colors, pixel mosaics, fireworks text, photo‑reconstruction from rectangles, image‑derived primes, AI clocks, etc.

Languages, interpreters, and deep esoterica

  • People implement interpreters/compilers for BASIC, Forth, C subsets, Brainfuck, Lua, C in Python, esolangs like Piet and Funciton, SUBLEQ and FRACTRAN, and type‑level programming in TypeScript.
  • Some golfed or obfuscated entries (IOCCC, tiny RISC‑V/MIPS emulators, 4004 Linux stunt) are celebrated as “beautifully pointless.”
  • Others build abstract math toys (ordinal notation systems, combinator calculi, binary lambda calculus, exotic calendars).

Bots, generators, and odd UIs

  • Markov bots trained on chat logs, issue trackers, or political tweets mimic speech with absurd results.
  • “Fake activity” tools simulate busy terminals, scrolling logs, or Git histories.
  • Novel encodings: IPs as haiku, emoji short URLs, ASCII bonsai, QR‑to‑QR messaging, comment randomizers, etc.

Games, simulations, and physical gags

  • Many write clones or twists on classic games (Tetris, roguelikes, match‑3, Minesweeper variants, Pong as cellular automaton, Sudoku solvers).
  • Others build galactic or ecosystem simulations, particle “water,” demo‑scene intros, and sound‑based visualizations.
  • Hardware hacks include door or tunnel sensors playing Mario sounds, heart‑rate displays, and “magic 8‑ball” devices.

Pranks, Easter eggs, and workplace antics

  • Stories include subtle window‑nudging hacks, DVD drive openers, joke CLI tools, Slack/IRC bots, and hidden Easter eggs in shipped software.
  • Some automate annoyance (fake alerts, spinning CPU to warm a snack, trolling managers with over‑engineered helpers).

Learning and unexpected usefulness

  • Many describe these as vehicles to learn graphics, CV, numerics, compilers, networking, or JS optimization.
  • A recurring motif: projects later find niches (e.g., analog clock readers adapted for pressure gauges, color‑palette extractors for design, custom CAD in PostScript, niche automation tools).