Here's another Haskell example where I'd be interested to see a Rust counterpart. It's a red-black tree implementation where the tree invariants are enforced by types. The code would less ugly with more recent GHC features, but same idea.

https://gist.github.com/rampion/2659812

https://old.reddit.com/comments/ti5il

Can't think of anything.
The novelty must have worn off over time.
Or maybe my mind doesn't get blown easily.