At the moment, Python is the language I am most proficient with and my go-to language. I definitely appreciate the functional aspects that it has incorporated (list/dictionary comprehensions, functions like map, zip, reduce, and anonymous functions with lambda.) In 2014, however, I'm planning to gain some proficiency with something close to a Haskell, OCaml, or Lisp dialect. Hoping to hear back from someone who has done some "heavy lifting" with one of those...