A typeface of your own, drawn letter by letter and exported as a font file you can install and type with.
A brush and an eraser give a letter its shape, a pen draws corners and curves, single points pull the outline where you want it, and a pixelate tool breaks an edge into squares. Low floor, high ceiling: one stroke is already a letter, and after that you can argue with every point in it.
Each letter starts empty, with the original showing faintly underneath so there is something to aim at. One click drops that outline into the letter if you would rather edit than draw. Letters you leave alone go into the font as they were, so you can type with a half finished alphabet from the first letter on.
136 characters with Czech diacritics, plus the marks the accented ones are built from, sidebearings you can drag, a line to type test on, and the finished set downloads as a TTF. The work stays in the browser and a project file carries it anywhere.