I’ve been doing ruby for 10 years now, previously PHP for 6 and some time in perl and java. I have a short bio here about how I ended up where I am with programming. I also blog about ruby there because Ruby is Awesome! I always heard it was good to learn a functional programming language. After dabbling in scala and a tiny bit of haskell, I have settled on Clojure.
Clojure has the ability to be very compact and concise when describing how to solve a problem similar I think to how Ruby can be.
I dabble in most new languages if only to get a little taste so I could speak somewhat intelligently about them. Clojure is what I turn to for a break from ruby and the normal day to day work as a consultant. Maybe eventually I can turn clojure into my day-job but for now it remains on the side. :)