At this point I think I've used Ruby more than any other language in my life. I love how I can write clean, concise, and readable code in Ruby without having to think much about it. I really love the testing tools and community that Ruby has. Ruby has also greatly influenced two languages I really love:
Elixir - Functional programming language heavily inspired by Ruby and runs on the [Erlang VM](https://www.wikiwand.com/en/BEAM_(Erlang_virtual_machine)) which makes it easy to write concurrent/parallel code..
Crystal - A compiled and very performant language that's statically typed (with inference) that's heavily inspired by Ruby syntax. A lot of the Ruby code I've written just works in Crystal.