Free API web services

Very concise list of free Web APIs: http://www.programmableweb.com/apis/directory
It is good start for testing REST API calls in your application.

Spring examples from Spring engineer

Good source of spring example:
https://github.com/joshlong
https://github.com/joshlong/a-walking-tour-of-all-of-springdom

http://marakana.com/s/post/1394/multi_client_development_with_spring_josh_long_video