If you already have Maven installed, then GMaven is the quickest path to running some Groovy tools!
Provides very convenient command-line access to the Groovy language:
Which should look something like this:
For more information please see the documentation for Groovy Shell.
For folks that prefer a GUI over command-line access:
After running, Maven will spit out something similar to this:
And then display the GUI console window, waiting for it to be closed before continuing:
For more information please see the documentation for Groovy Console.