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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.

The first episode of Mike Zamansky's Using Emacs series, covering setting up the package manager for new Emacs users as a start toward customization and efficient editing.

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.

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.

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.

The first episode of Google's Machine Learning Recipes series. It introduces machine learning and builds a first supervised-learning classifier in about six lines of Python using scikit-learn.

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.

GE Lighting's official how-to for factory resetting C by GE smart bulbs, using a long sequence of precisely timed on and off cycles.

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.

A short first episode in Zaiste's Doom Emacs series, showing how to get started with Doom, an Emacs configuration aimed at Vim users. It presents Doom as a polished, fast, batteries-included distribution.

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.

Day 1 of Handmade Hero's introduction to C on Windows, covering setting up Visual Studio, creating a Win32 project, the WinMain entry point and writing a first function. It is the starting point for Casey Muratori's from-scratch game series.

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.

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.

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.