Custom verbs aren't really necessary. You can do some of your "method" naming in the URI. One example could be: /sum?number=1&number=2 which, when a GET is issu

Custom verbs aren't really necessary. You can do some of your "method" naming in the URI. One example could be: /sum?number=1&number=2 which, when a GET is issued, will return a representation of 3. If you need to perform some action that can be expected to take time, you can issue a POST request, which can give you a new resource that reports back on its current state. An example could be: POST /printer with the request body containing the document to print. It could assign a URI that tells you the status of the document (location in queue) and you can DELETE it if you no longer want to print the document.