physical access

Kristy Viers demonstrates the iPhone Magnifier combined with VoiceOver to describe the user's surroundings. She shows how the built-in feature reports scenes, faces and lighting.

Lock-picking YouTuber Bill Johnson (BosnianBill) explains how to choose a high-security lock and why, showing examples and comparing designs. It covers what makes some padlocks more pick-resistant than others.

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.

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 Eater finishes building a minimal VGA video card from logic circuits. He explains analog RGB signals, stores an image in an EEPROM and builds a simple digital-to-analog converter to display it.

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.

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.