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Ben Krasnow of Applied Science shows how to make and test YBCO high-temperature superconductor with a kiln and eBay chemicals. He demonstrates flux pinning and shows a close-up of the crystal structure.

The Townsends channel shows how to make mushroom ketchup, a popular 18th-century sauce, in period style. It includes the history and a recipe and links to a blog post on whether George Washington used ketchup.

A reupload of Joel Spolsky's talk teaching spreadsheet users the Excel features they are probably missing, such as keyboard navigation, named ranges, tables and lookups. The original disappeared and this copy comes from the Wayback Machine.

David Beazley's PyCon 2019 tutorial derives the lambda calculus from the ground up in Python, using only single-argument functions. He builds booleans, numerals and more with no other language features.

Jim Pavloff rebuilds the Prodigy track Smack My Bitch Up in Ableton, identifying the samples used and recreating the track by hand.

Day 1 of Casey Muratori's Handmade Hero, a live-coded game built from scratch in C on Windows. It reviews C on Windows, sets up a minimal build system and WinMain entry point, and shows a first MessageBox.

In this first Crust of Rust episode, Jon Gjengset live-codes an example that needs multiple explicit lifetime annotations. Along the way he covers string types and generics over a custom trait.

A two-hour NANOG tutorial by Richard Steenbergen aimed at network engineers, covering optical networking technologies. This is the updated 2017 edition of a recurring talk.

The first part of a ShaderToy live-coding series that lays the groundwork for The Drive Home, a rainy night-traffic shader. It covers basic setup and builds toward rain and bokeh effects.

Dodoid gives an in-depth look at an SGI Onyx RealityEngine2, a $250,000 graphics supercomputer from 1993, covering its history, a physical overview, a teardown and some demos and games.

Chess player John Bartholomew plays opponents rated below 1000 on Chess.com and comments on optimal strategy and typical mistakes at that level. It is part of his Climbing the Rating Ladder series.

Technology Connections shows a cheap method for capturing analog video: a composite-to-HDMI upscaler feeding an HDMI capture dongle, aimed at digitizing home movies and VHS tapes.

Mathologer shows a simple idea, the commutator, that lets anyone who can solve the first layer design their own full Rubik's cube solution. The same idea carries over to other symmetric twisty puzzles such as the Megaminx.

Ben Krasnow of Applied Science uses an antique 4x5 view camera to make high-resolution photolithography masks in a home shop. He photographs a poster-sized printout onto litho film to get features around 20 microns.

First of a three-part tutorial series on the i3 tiling window manager for Linux. It explains what i3 is, how to install it on Ubuntu, and how to use it.

Ben Krasnow of Applied Science explains how electrophoretic e-paper displays work and how he modified the driver firmware and waveform lookup tables of a 4.2-inch panel to reach roughly 3Hz partial refresh. It covers the tweakable constants in the refresh process and touches on colored e-ink microcapsules.

DIY Perks shows how to turn old or smashed TVs and monitors into realistic artificial window lights, using the backlight and Fresnel lens to simulate distant daylight.

Kenneth Finnegan shows how USB-C Power Delivery trigger boards like the ZY12PDN negotiate 5V to 20V so you can power projects from a USB-C charger, including the color coding for each voltage.

Ben Eater explains how the PS/2 keyboard interface works, covering its clocked serial protocol and scancodes. He builds up the hardware-level understanding needed to read keypresses.

Inigo Quilez live-paints a mountain landscape using only math in a shader, building up from a basic polynomial noise surface through fractal terrain, lighting and atmosphere. The code runs in real time on Shadertoy so viewers can edit it as they follow along.

Bisqwit builds a Doom or Duke Nukem 3D style software-rendered 3D engine in C from scratch, supporting non-Euclidean geometry. It covers vector rotation and portal rendering with sped-up, tool-assisted coding.

The first video in Photon of Scoopex's Amiga hardware programming series. It shows how to set up an assembler and write a minimal 68000 program that waits for a left mouse click.

Bisqwit writes a NES emulator in C++ in about 15 minutes of tool-assisted, sped-up coding, narrated with captions. It shows an accurate emulator built with a compile-time generated 6502 instruction table. Part 2 covers compiling and running it.

NightHawkInLight shows how to make radiative sky cooling paint from grocery and hardware store materials, including a novel calcium carbonate microsphere synthesis. The paint can cool a surface below ambient air temperature in direct sunlight without electricity.

Ian Hubert shows quick, unconventional tricks for greenscreen compositing in Blender, as a follow-up to his motion tracking video.

Anders Brownworth gives a basic visual introduction to blockchain using an interactive web demo, covering SHA256 hashes, blocks, chains, distribution, tokens and coinbase transactions.

A three-hour PyCon 2016 tutorial by Christophe Pettus that orients Python developers to PostgreSQL. It covers installation, administration, and use, including vacuuming, MVCC, replication and backups.

Ben Eater writes a program in a made-up machine language and walks through the control logic an 8-bit breadboard CPU needs to execute it. It is part of his build-an-8-bit-computer series.

ElectroBOOM's Mehdi Sadaghdar explains how a full bridge rectifier works, the building block of AC to DC converters, with his usual humor and a demonstration of the circuit.

James Hoffmann demonstrates his technique for a clean, sludge-free cup from a French press: stir, break the crust, wait, and carefully pour. It is a four-minute guide.

The first episode of a screencast series building djb's redo build system from scratch in Haskell. It explains the purpose of redo, writes initial code and sets up a GitHub repository.

Inigo Quilez live-codes a painting using only mathematics in a shader, building it up step by step. The linked Shadertoy source shows the result.

DIY Perks builds a webcam mod using a two-way mirror in a box so the camera sits behind the screen image. This allows real eye contact on video calls.

Harry Schwartz gives a roughly hour-long tour of Emacs Org mode as an outliner, task manager, markup language and agenda tool. He demonstrates how he uses it for documents, presentations and todo lists.

Big Clive shows how to pick up discarded disposable vape devices from the roadside and extract the rechargeable lithium cells inside. He explains why these devices contain the same circuitry as rechargeable ones and how to reuse the cells.

A step-by-step guide to building a lifter, a small triangular ionocraft made from balsa wood, aluminum foil and thin wire, powered by a high-voltage supply. It also shows high-voltage safety practices.