A lot of the projects I've been thinking about for the past decade relate to a dynamic searchable ontology. It keeps coming up again in one shape or another, so I bit the bullet, wrote a few notes, then knocked out a draft of the prototype and a quick blog post.
Pretty sure that this is approximately the right shape for the data layer of the ideas I've been thinking about for a while; once it's sorted, I can use it as a kernel & data layer in other systems.
http://pnathan.com/blog/coding-and-software/2018-08-28-A-Common-Data-Model.html