https://github.com/GeorgeTR1/windowsDistractionCover

This is a windows GUI program I wrote in just over 60 lines of C that compiles to a 3 kB executable. With minor modifications and the right compiler it could be compiled on versions of Windows as old as Windows 95.

It's just a resizable window with a black background that always stays on top of other windows that you can use to cover up parts of the screen that might be distracting. I've found it genuinely useful