I spent a while chasing the weirdest languages I could find (relative to everything else I knew at the time), but feel like I've gotten to the point of diminish

I spent a while chasing the weirdest languages I could find (relative to everything else I knew at the time), but feel like I've gotten to the point of diminishing returns. I've been studying types and semantics instead. I do most of my actual programming in Lua + C and an in-house language. I really like Erlang (but haven't worked on the right kind of projects lately), and I also prototype stuff in Prolog. I would love to have a more modern dialect of Prolog, designed primarily for embedded use as a C library (much like Lua, and ideally with a similar C FFI). It's a cool language, but it's also really strongly skewed towards certain problem domains. Lua has taught me that when a language can delegate its weak points to a symbiotic language, it can stay really small and focused on its strengths.