REST API working code examples?

Your developers will love <3 this JavaDoc documentation of the REST API which also contains example URLs: http://lithosphere.lithium.com/t5/Developers-Knowledge-Base/Admin-Guide-REST-API-JavaDocs/ta-p/5966

...next step would be having them sign up here on Lithosphere and search for "REST API" + the topic they want to use the API with.
Good start is this collection of search examples: http://lithosphere.lithium.com/t5/Developers-Knowledge-Base/Working-with-Rest-API-search/ta-p/39942

Finally if they are into content browsing here are items tagged with "REST API": http://lithosphere.lithium.com/t5/tag/rest%20api/tg-p )

Another tag I like to use is "code sample":

http://lithosphere.lithium.com/t5/tag/code%20sample/tg-p