Elixir is a really cool language, and also a great way to learn functional programming. But more than that, it gets all the non-languagy stuff right. The build system is amazing, your code hot-reloads out of the box, dependency management is very well done (source-only, git-friendly, project-local, etc), the community is very friendly and going fast.
And code scales by default. I might exaggerate here, but sometimes it feels like need to really try to write code that's hard to spread across servers. If you consider it's non-trivial to even use all your CPU cores on Node.js, the Erlang VM will blow your mind.