Split-flap displays are electromechanical display devices, which were common in airports or railway stations a few years ago.Unfortunately, most of them are gone and replaced by LED displays. Why not create a DIY version of it?
G-Code (or RS-274) is a widely used protocol for CNC machines. I have added vinyl cutting capabilities to the Shapeoko desktop CNC recently (see DIY Vinyl Cutting Drag Knife for Desktop CNC), however cutting vinyl with a drag knife is whole different story compared cutting materials like wood or aluminum. As with many other things, it is about handling all corner cases properly.
A desktop CNC is a great addition to any 3D printer or laser cutter. I consider them ‘the trinity’ for any maker garage. While a desktop CNC is great for wood and some metals like aluminum or brass, it would be great to extend the infrastructure with something more: vinyl cutting. And with this the idea to have cool sticker on my laptop lid: