We miss the slide rule. It isn’t so much that we liked getting an inexact answer using a physical moving object. But to successfully use a slide rule, you need …read more (https://hackaday.com/2026/01/23/size-and-units-really-do-matter/)

The Defunct Scooter Company, and the Default Key
https://hackaday.com/2026/01/23/the-defunct-scooter-company-and-the-default-key/

Äike were an Estonian scooter company, which sadly went bust last year. [Rasmus Moorats] has one, and since the app and cloud service the scooter depends on have lost functionality, …read more (https://hackaday.com/2026/01/23/the-defunct-scooter-company-and-the-default-key/)

Hackaday Podcast Episode 354: Firearms, Sky Driving, and Dumpster Diving
https://hackaday.com/2026/01/23/hackaday-podcast-episode-354-firearms-sky-driving-and-dumpster-diving/

Hackaday Editors Elliot Williams and Al Williams took a break to talk about their favorite hacks last week. You can drop in to hear about articulated mirrors, triacs, and even …read more (https://hackaday.com/2026/01/23/hackaday-podcast-episode-354-firearms-sky-driving-and-dumpster-diving/)

Wired to Wireless: ESP32 Gives Your USB Keyboard Bluetooth
https://hackaday.com/2026/01/23/wired-to-wireless-esp32-gives-your-usb-keyboard-bluetooth/

Few things rival the usability and speed of a full-sized keyboard for text input. For decades, though, keyboards were mostly wired, which can limit where you use your favorite one. …read more (https://hackaday.com/2026/01/23/wired-to-wireless-esp32-gives-your-usb-keyboard-bluetooth/)

PLA Mold To Plaster Bust, No Silicone Needed
https://hackaday.com/2026/01/23/pla-mold-to-plaster-bust-no-silicone-needed/

3D printing is wonderful, but sometimes you just don’t want to look at a plastic peice. Beethoven’s bust wouldn’t look quite right in front of your secret door if it …read more (https://hackaday.com/2026/01/23/pla-mold-to-plaster-bust-no-silicone-needed/)

Lead Acid Battery Upgraded to Lithium Iron Phosphate
https://hackaday.com/2026/01/23/lead-acid-battery-upgraded-to-lithium-iron-phosphate/

Lithium batteries have taken over as the primary battery chemistry from applications ranging from consumer electronics to electric vehicles and all kinds of other things in between. But the standard …read more (https://hackaday.com/2026/01/23/lead-acid-battery-upgraded-to-lithium-iron-phosphate/)

Polymer Skins That Change Color and Texture When Exposed to Water
https://hackaday.com/2026/01/23/polymer-skins-that-change-color-and-texture-when-exposed-to-water/

Researchers at Stanford University recently came up with an interesting way (Phys.org summary) to create patterns and colors that emerge when a polymer is exposed to water. Although the paper …read more (https://hackaday.com/2026/01/23/polymer-skins-that-change-color-and-texture-when-exposed-to-water/)

Beer Keg Plumbing for a Liquid Rocket
https://hackaday.com/2026/01/23/beer-keg-plumbing-for-a-liquid-rocket/