locks

A short Vox video on Barcelona's superblocks, an urban design approach that closes interior streets to through traffic to return space to pedestrians.

A scene from The Big Short in which Jared Vennett pitches credit default swaps on mortgage bonds to a hedge fund team, using a Jenga tower to illustrate collateralized debt obligations.

A short How to ADHD explainer, featuring Brendan Mahan, on why simple tasks can feel impossible for people with ADHD. It introduces the 'wall of awful', a pile of past failures, shame and anxiety that builds up in front of a task and blocks starting it.

A five-minute CGP Grey explainer arguing that a phone is effectively an extension of your mind, and that any backdoor or master key into encrypted devices will inevitably be abused or leaked. It frames the encryption debate as locks that are either unbreakable or absent.

An MTA video on communications-based train control, the system meant to replace the New York City subway's century-old signaling. It also shows the mechanical interlocks and signals in use today.