RE: POST but not multipart/form-data for file upload

> 
> Can I upload a file via the POST method, but not using 
> multipart/form-data?

The HTTP specification allows this just fine. Browsers don't provide easy
access to it though.

Both the client and the server have to understand what the bytes after the
headers look like.
This is indicated via the Content-Type: header. You can use Content-Type:
text/xml and send XML - your server probably can be coded to understand this
pretty easily.

You may be able to do this in some browsers that support script and have
some helper components - like XMLHTTPRequest in IE and XMLHttpRequest in
Mozilla.