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Half as Interesting explains why airlines flew empty 'ghost flights' out of Heathrow to keep their landing slots under use-it-or-lose-it rules.

Veritasium explains why the one-way speed of light has never been measured, only the round-trip speed, since measuring it requires synchronized clocks that assume the answer. It explores the implications for relativity.

A PBS clip in which Richard Feynman explains the strange nature of light and electromagnetic radiation. He conveys how little of it we actually see and how radio waves are present everywhere.

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.

Technology Connections experiments with filtering white and colored LEDs to make holiday lights look less garish. He explains why narrowband LED strings look harsh compared with incandescent bulbs.

An 8-minute explainer on the Lightning Network and how it relates to Segwit, Bitcoin and Litecoin. It covers how off-chain payment channels route payments to scale blockchain transactions.

A short look at CoeLux, an artificial skylight that recreates the scattering process that makes the sky look blue, producing a convincing illusion of distant sun and depth.

A SIGGRAPH 2013 demo from Douglas Lanman and NVIDIA of near-eye light field displays, which allow much thinner head-mounted displays that still show accurate focus and depth cues.

A 2017 video arguing that banks and Blockstream steered Bitcoin toward the Lightning Network. It is partisan commentary from the Bitcoin Cash side of the scaling dispute.

Technology Connections complains about the harsh, overly blue color of modern LED Christmas lights and tries more fixes for them. It follows earlier videos by the same creator on holiday lighting.

A man with no flight instruction and only desktop flight simulator experience attempts to take off and land a Cessna 172, with a commercial airline instructor aboard who gives no help. The flight came out of a prop bet.

Technology Connections explains how LED traffic lights, which do not melt snow, drew complaints and were blamed for accidents. He uses it to illustrate the 'but sometimes' fallacy against new technology.

Professor Mike Merrifield of Nottingham explains in a mostly uncut conversation why light travels slower in glass. He treats light as a wave and describes how the material's electrons produce secondary waves that combine to slow it.

PBS Space Time argues that the speed of light is better understood as the speed of causality, the universal limit on how fast cause and effect propagate. Light travels at that speed because it is massless, but the limit itself is a property of spacetime.

Fermilab's Don Lincoln explains why light travels slower in water and glass. He knocks down common wrong explanations such as absorption and re-emission, then gives the wave-mechanics reason tied to refractive index.

ScienceClic explains why nothing can go faster than light by treating motion through space and time together, so everything moves at the speed of light through spacetime. It uses animated visuals to cover relativity basics in 12 minutes.

The Slow Mo Guys visit a lab with a camera capable of filming at 10 trillion frames per second, fast enough to see light travel. They show the setup and the resulting footage.

Wendover Productions explains why Boeing's efficient 787 beat Airbus's giant A380, contrasting hub-and-spoke with point-to-point routes. It covers the economics of long-haul flights.

A Fully Charged episode on Electroflight, an early-stage project to build a fully electric racing plane that can exceed 300 mph. It features two motors driving contra-rotating propellers.

AVweb's flight trial of Garmin's Emergency Autoland system, which flies a plane to a runway and lands it when the pilot cannot. It is part of Garmin's Autonomi automation on the G3000 avionics.

Real air traffic control audio of the Air Astana flight whose flight controls had been wired in reverse by a maintenance error. The pilots struggle to keep control while ATC tries to help.

Not Just Bikes explains how Dutch traffic lights use early detection, transit priority and conflict-free design to cut waiting. The aim is to move as many people as possible rather than as many cars.

First part of a six-part recording of the 1973 Lighthill debate on AI, where Sir James Lighthill's critical report on AI research was contested by figures including McCarthy and Michie.

A full piano performance of Beethoven's Piano Sonata No. 14, the Moonlight Sonata, with all three movements: Adagio sostenuto, Allegretto and Presto agitato.

A five-minute lightning talk from React.js Conf 2016 by Elie Rotenberg on protecting the DOM from tampering. It shows how React tree obfuscation (react-armor) can shuffle class names, tags and tree structure to defeat CSS-selector-based ad blocking.

AVweb's Paul Bertorelli explains why general aviation has failed to replace leaded avgas, blaming industry inertia, bureaucratic delay and an exemption that removes the incentive. This is part one of two.

AVweb's Paul Bertorelli explains in part two of a series why general aviation has not replaced leaded avgas. He covers industry inertia, bureaucratic delays and the exemption that lets the industry keep using lead.

Nature video showing MIT researchers flying the first plane with no moving parts, powered by an ion drive that creates an ionic wind from high-powered electrodes. The 5m-wide craft flies across a sports hall.

Inventor Mary Lou Jepsen demonstrates using red light and sound to see inside the body and brain, aiming at tumor detection and neural activity measurement, and potentially a cheaper wearable MRI replacement.

Asianometry explains the EUV light source inside ASML's lithography machines, where lasers hit falling tin droplets twice to produce 13.5 nm light. It walks through the engineering of the droplet generator, the pre-pulse and main laser, and the plasma that results.

A five-minute lightning demo of VisiData, a terminal tool for exploring and manipulating data. It uses two months of NYC 311 complaint data to drill down, plot points on a virtual map and save selected rows.

A WSJ report on China's 'dark factories', highly automated plants run by robots with little human presence, visiting Zeekr's EV factory. It covers Chinese labor costs, automation and overproduction in the EV industry.

A six-minute sketch from That Mitchell and Webb Look in which a speaker argues you should never drink more than slightly less than two drinks, the mildly intoxicated sweet spot before drunken madness.

Footage of Richard Box's art installation in which fluorescent tubes light up in the ground under high voltage power lines, showing the electric fields they produce.

Highlight clip from the 2021 Free Expression Awards honoring YouTube CEO Susan Wojcicki. The video became notable for its overwhelmingly negative like/dislike ratio.

A KRAZAM comedy sketch in which Makro walks through the latest Microsoft Office 365 Excel update in a mock stream highlights format.

SuperfastMatt looks at how the Tesla Model S retracting door handles were redesigned over time, from many parts to a motor plus sensor, with a focus on engineering and reliability.

Huygens Optics shows how DIY photon sieves shape a laser's wave front, explaining how they differ from zone plates and how aperture count affects the focal point, with time-resolved visualizations of the diffraction.

Day9 gives a passionate first look at what his StarCraft: Brood War Remastered series will teach. He argues Brood War is primarily a real-time game and only secondarily a strategy game, making the commander fantasy a matter of mechanics.

KRAZAM parody sketch in which an Excel streamer, Makro, treats the XLOOKUP function as a game-breaking meta change, spoofing e-sports commentary.