The DSpi is a handheld with a clamshell design, two small screens, and an open source design – you can’t actually buy one, but you can find design files, software, and a parts list in the developer’s ...

Beginner tip: Find a toehold. Almost all Easy (and some Medium) puzzles will have an obvious starting point, where only one domino makes logical sense. These “toeholds” will help you finish the rest ...