fuzzyBSc - I really suggest not adding arbitrary methods to HTTP. Its standard practice for firewalls to take a deny unknown approach to handling unknown methods.
I think a more useful way of looking at HTTP methods and urls is from a message passing point of view:
GET = pass a query message to the object at the URL with parameters as per the URL.
POST = pass a mutating message to the object at the URL with parameters as per the URL/uploaded-message.
This gives you the as much flexability as changing the HTTP Method might, but makes the semantics of your request clear to all parties, which will aid debugging, reduce negative interactions with intercepting or mandatory proxies ...