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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.

The Thought Emporium shows how to receive clear images directly from GOES-15, 16 and 17 and Himawari 8 geostationary weather satellites with software-defined radio. It covers the extra effort needed to receive GOES data.

NightHawkInLight shows how to make ultra-white radiative paint that cools surfaces below ambient temperature without electricity. He walks through the research papers and the household-materials process.

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.

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.

David Sanders gives the first part of a two-part introduction to the Julia programming language at SciPy 2014. It walks through the language's basics and its appeal for scientific computing.

Allieway Audio gives an informal introduction and live-coding demo of ORCA, a free esoteric programming environment for building procedural sequencers from Hundred Rabbits. It walks through the interface and how to make music with it.

A long livestream of George Hotz live-coding a toy SLAM implementation, twitchslam, over two days in May 2018. It is an unedited session of Python programming with computer vision and visualization.

Tech Ingredients shows how to build a liquid panel with a specialty paint that, placed outside, cools below ambient air temperature. It demonstrates radiative sky cooling.

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 roughly 45-minute vintage US military instructional film that gives a comprehensive overview of celestial navigation, covering sextant use and the theory behind lines of position.

A short video advising how to handle a police stop by politely refusing searches and not answering questions, citing Fourth and Fifth Amendment rights.

Tech Ingredients shows how to make a homemade radiative cooling paint, with a custom liquid panel that cools below ambient temperature outdoors. The video covers the materials and how to apply the paint.

Tsoding live-codes a JSON parser from scratch in Haskell in about 111 lines, using only the standard library. It is an edited Twitch stream that explains the intuition behind parser combinators, functors, applicatives and monads.

The UK DVSA's one-minute guide to the hazard perception part of the driving theory test, covering when to click and how to score well.

An episode of FunFunFunction explaining monads in JavaScript as functors that also implement flatMap. It builds on the preceding functor episode and works through code examples.

In a long live-coding session, Andreas Kling works on making the Cookie Clicker game playable in the Ladybird browser from SerenityOS. He tracks down bugs in the browser engine and fixes them.

Phoenix creator Chris McCord builds a real-time Twitter-style app live with Phoenix LiveView 1.5 in about 15 minutes. It shows interactive, real-time updates without writing JavaScript.

Marco Baringer's tutorial video on SLIME, the Emacs mode for developing Common Lisp. It demonstrates the interactive workflow of working against a live Lisp image.

Jon Gjengset's roughly four-hour live stream implementing part of a BitTorrent client in Rust, following CodeCrafters' test-guided challenge. He builds from scratch and shows idiomatic error handling along the way.

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.

Inigo Quilez live-codes the "Happy Jumping" animated scene in a Shadertoy GLSL shader over about six hours. He builds the raymarched character step by step, explaining the math and procedural techniques, with checkpoints linked for each stage.

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.

Dan Worrall explains when higher sample rates help in recording and mixing, and when they do not. He goes into oversampling versus higher sample rates, and aliasing in distortion plugins.

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.

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 how to use Blender's motion tracking to turn ordinary footage of a room into a stylized digital environment for an indie film. It is a quick, practical walkthrough in his loose, lazy-tutorial style.

Alan Becker's short series on the 12 principles of animation, covering squash and stretch, anticipation, staging, timing, arcs, appeal and the rest. Each principle gets a brief animated illustration.

CuriousMarc inspects a newly arrived Teletype Model 19, an early military unit built around a Model 15 keyboard and printer, after an initial rough cleaning. It is the first part of a restoration series and touches on 5-bit Baudot code.

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.

The first stream in the Emacs From Scratch series, building a custom Emacs configuration from zero while teaching basics. It covers a usable baseline setup and the packages for completion, themes and productivity.

This Old House's Ross Trethewey explains MERV filter ratings and how air filtration works, then shows how to build a localized DIY air filter, including a box fan with multiple filters.

Matt Risinger covers installing a Zehnder ERV fresh-air system in a tight passive house, explaining balanced ventilation, the benefits of heat recovery and the costs involved.

A screencast tutorial on Specter, a Clojure library for navigating and transforming nested data structures declaratively, demonstrated in a REPL.

A how-to video on datamoshing, the glitch-art technique of removing keyframes so that motion data smears across video. It walks through the tools needed, such as ffmpegx and Avidemux, though the author notes parts are outdated.

A This Old House segment where Richard Trethewey installs a heat exchanger that uses waste heat from a central air conditioner to heat a swimming pool.

Imphenzia's 83-minute tutorial covers the low poly modeling techniques he learned over five years of Blender use, with timestamps from navigation and extrusion onward. It uses Blender 2.83 with default keys.

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.

Andrej Karpathy builds a bigram character-level language model from scratch, introducing torch.Tensor and the framework of training, sampling and loss evaluation. It is the first step toward a GPT-style Transformer in his makemore 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.