I plan to explore the Groovy Kata path. Is there a source similar to RubyQuiz for Groovy Katas?
Browse Groovy Koans at https://github.com/cjudd/groovy_koans .
Also see http://github.com/nadavc/groovykoans for Groovy walkthroughs, covering:
Disclaimer: I wrote them;)
Coding Kata is a site that provides cathadas and code examples in several JVM languages, Groovy being one of them.
Unfortunately, the Java-centric Coding Kata site has been disabled. You can try the .Net version
I highly recommend Groovy Metaprogramming Coans .
This is a terrific source to learn about metaprogramming with Groovy.
Spend any quiz and implement it in your chosen language. There are many cases: some guy decided PythonChallenge almost completely in Haskell.
I liked solving math problems with Groovy, Kotline, etc. on the Euler project website → http://projecteuler.net/
Pretty decent site for Koans http://www.groovy-koans.org/