OCaml. Industrial strength. Multi-paradigm. OCaml is a great language for learning about languages. It embraces functional, imperative, and object oriented styles. It's based on ML, a language which informed the design of many rising languages such as Elm, Clojure, and Elixir. This language will teach us about an alternative universe where objects and functions play together like lions and lambs.

Pony. OOP meets actors, capibilities, and high-performance. Pony is another language that has a sophisticated take on what object orientation could be. Pony values correctness to the extreme, to the point where most runtime errors are completely removed from the language. The actors-based concurrency model is nonblocking and the capibilities system allows correctness proofs. Don't wish you had a pony. Ride one.

Rosie Pattern Language. Regular expressions reimagined. The Rosie Pattern Language (RPL) takes the "press" out of "regular expressions". By providing a consistent type system and bindings into expression definition, it's much easier for new code to incorproate checks for common patterns like emails or URLs. RPL allows integration with other languages or processing from the command line. Pattern recognition doesn't have to hurt.