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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.

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.

A three-minute Emacs Rocks screencast by Magnar Sveen demonstrating paredit, which edits Lisp code structurally as a tree of s-expressions rather than characters.

A University of Michigan Medicine demonstration of building a cheap DIY air purifier from a box fan and a HEPA or high-MERV filter using hardware-store parts. It explains why this helps against dust, smoke and viruses and ties it to local air quality readings.

Terry Moore's three-minute TED talk showing a better way to tie shoes, replacing the common granny knot with a square knot so laces stay tied.

The trailer for Tim Hunkin's series The Secret Life of Components, eight guides to mechanical and electromechanical parts for designers and makers.

GE Lighting's official how-to for factory resetting C by GE smart bulbs, using a long sequence of precisely timed on and off cycles.