I guess I really don't get REST, shipping a REST client for a specific API is a thing. If you're gonna provide a client, who cares if it's really REST after all?
I guess REST is there to make it easier for other people to implement your API. SOAP was hard without libraries, I can hit your REST endpoint with curl.
I must admit that was my initial reaction when I saw the title of this article - I tend to regard curl as the universal RESTful API client. I don't think I've written or consumed a RESTful API where I didn't spend a fair amount of time interacting with the system through curl.
cURL works fine for RPC-style or non-RESTful clients too. Instead of "-XPUT" you make your URL end with /foo/addfoo or something. And who cares if the FooID is in the URL or in postdata? In fact, cURL makes it easier to add another data parameter than change the URL.
