A collection of interesting links I found on the World Wide Web:

Software

• SageMath is a nice Python math package.
• FLINT is a number theory library for C.
• Neovim is a rich Vim-based text editor that I personally use.
• Caddy is a modern web server with automatic SSL. This website is hosted on it.
• suckless.org has a collection of minimalist software for Unix.
• FFmpeg is an extremely powerful media processing tool.
• nnn is a terminal file manager.
• copyparty is a portable file server.
• Ghidra is a powerful reverse engineering tool.
• strace is a Linux syscall tracer.

Games

• OpenTTD is an open-source transport tycoon game.
• OpenRCT2 is an open-source RollerCoaster Tycoon 2 clone.
• GZDoom is a source port of id Software’s original Doom engine.
• doomgeneric is easily portable Doom.
• NetHack is an old but still maintained open-source roguelike.
• Universal Paperclips is an online game about an AI making paperclips—what could go wrong?
• The Powder Toy is a relatively modern take on the old falling sand game.
• Luanti, formerly Minetest, is an open-source voxel game similar to Minecraft.

OS dev

• OSDev wiki has useful information for writing a toy OS. Articles vary in quality but are still quite helpful.
• 9front is a fork of Plan 9 from Bell Labs. An interesting little OS that takes the Unix philosophy to the next level.
• OpenBSD is a powerful free Unix OS. The source code is very clean and can act as a useful reference.
• SerenityOS is a quite advanced hobby OS. Development is led by Andreas Kling of Ladybird browser fame.
• ToaruOS is another interesting toy OS.
• SkiftOS is yet another homebrew OS.

Radio/Satellites

• RTL-SDR is a small SDR dongle that lets you listen to a wide spectrum of radio frequencies.
• Gqrx is SDR software for Linux.
• SDRangel is a very powerful piece of SDR software with a lot of supported modes.
• WebSDR is an HF SDR receiver located at the University of Twente in the Netherlands.
• tracksat.space is a nice little site for tracking satellites.
• SatDump is a program for decoding a wide range of satellite transmissions.

Websites

• Hacker News aggregates interesting articles and produces (mostly) high-quality discussion.
• http.cat explains HTTP status codes with cats.
• xkcd O-|—<
• The Onion, still producing hilarious stuff after some 40 years!
• EFF is the Electronic Frontier Foundation. They do a lot of good work defending digital rights and privacy.
• Neocities is a free, modern GeoCities-inspired website host. A lot of cool websites are hosted here!
• Decompiler Explorer is an online interface for decompiling binaries with several decompilers.
• LKML — the Linux kernel mailing list archive.
• Compiler Explorer is an online compiler and disassembler.
• awesome-selfhosted is an extensive list of software that can be self-hosted.
• Overleaf is an online LaTeX editor.
• Elixir is an amazing source code explorer, e.g., for the Linux kernel.
• Gruvbox Wallpapers is a collection of wallpapers that fit the gruvbox color scheme.
• FactorDB is an online integer factorisation database.
• GIMPS — the Great Internet Mersenne Prime Search.
• Stanford Encyclopedia of Philosophy is a very well-written online philosophy encyclopedia.
• Math LibreTexts is a repository of open-access math texts.
• ProofWiki is a wiki with proofs of mathematical theorems and definitions.
• OEIS is the On-Line Encyclopedia of Integer Sequences, a repository of known integer sequences.
• mandelbrot.site is a well-written Mandelbrot set explorer in the browser.
• erdosproblems.com catalogues around 1100 problems and conjectures posed by the great Paul Erdős.

Blogs

• nullprogram is Chris Wellons’s incredible programming blog.
• thephd is JeanHeyd Meneide’s blog about C/C++ stuff.
• Jacopo’s Lair has some useful articles about radio and weather satellites.
• Shtetl-Optimized is Scott Aaronson’s amazing blog, mainly about computer science.
• Astral Codex Ten and Slate Star Codex are Scott Alexander’s new and old blogs. Very well-written posts about a range of topics.
• Numb at the Lodge is extremely well-written and covers interesting topics—mostly philosophy-related. Sam Kriss is hands down one of the best writers on the internet.
• Noahpinion is Noah Smith’s economics blog.
• LOW←TECH MAGAZINE is a solar-powered website.

~more to come…