I would love this to be turned into a text editor. You set up a target, e.g. 20K chars and start typing away. No formatting, no distractions. The program always just shows the current line, or even just the 10 characters, while previous lines fade out into black with no way to reveal them. Only after hitting the target is the entire text revealed.

Optionally with some reward animation/sound after every target/10 characters.