There is an interesting post by Pratik Patel from last month's Atlanta Groovy and Grails (ATL2G) meeting. This video demonstrates using Groovy on Google AppEngine using the Groovy Gaelyk libraries. If you are interested in taking advantage of Google's cloud computing resources using Groovy, this is a good presentation.
More posts will follow with a brief written "How-to" and some twists on Pratik's demo.