AMMDI is an open-notebook hypertext writing experiment, authored by Mike Travers aka mtraven. It's a work in progress and some parts are more polished than others. Comments welcome! More.
The block-programming designs started here also made their way into the BioBike VPL, Enflame, and Vaguely. The source is on Github but it depends on a version of Mac Common Lisp and the Mac OS that has been obsolete for decades.
Vaguely is a tool/hack for exploratory data visualization, based on Vega-Lite, "a high-level grammar of interactive graphics". Vaguely is a partial translation of that grammar into a Scratch-like blocks interface, making it easier to experiment with different visualizations.