The purpose of this thread is to collect examples of systems that have particularly strong design in a certain area, or are exemplars of their design lineage, or are otherwise interesting and compelling in a way worth becoming familiar with.
This is not a complete or authoritative list! That’s why I’m making this a thread here, so we can all contribute based on our own experiences and priorities.
(Creating this thread required a burst of energy and inspiration that wasn’t quite enough to extend to explaining why everything on my lists made the lists, but I plan to edit and add further explanations later)