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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.

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.

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.

Inigo Quilez live-codes a cartoon character painting entirely from math, using signed distance fields in a Shadertoy shader. He explains each step of building the image from formulas.

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.

The first of a short series by Welch Labs on building a complete neural network in Python. It introduces the data and the architecture of a simple network before later parts cover forward propagation, gradient descent, and backpropagation.

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 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 woodworker shows how his table saw accident happened, why it happened and how to avoid a similar one. He describes severe hand lacerations from a blade contact.

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.

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.

A short video of stretching and hand exercises for preventing and easing tendinitis and carpal tunnel syndrome, from a percussion teacher. The exercises were shown to him by a doctor.

A short promotional video demonstrating a head-thumping technique that is claimed to relieve tinnitus. Covering the ears and tapping the back of the head is said to silence the ringing temporarily.

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.

David Beazley's workshop screencast builds asynchronous programming in Python from scratch, starting from callbacks and continuations and replacing threads to show how concurrency works underneath.

A 1993 Yoga Works video of the Ashtanga Yoga Primary Series led by Sri K. Pattabhi Jois, with senior students demonstrating. The class is filmed in classic style from the back of the room.