export from one server to another

HI there, I am thinking about building a partner network where partners can export content to my server which will then be imported. It should be as easy as possible for the partner and not rely on any special php functions. The best way to do this I guess is to deliver them a php file which will create a xml structure that I can import. The problem I have now is, how to transfer this xml-file to my server? Of course I could do this via FTP, but then they need to have FTP enabled inside their php installation. This might scare some partners away. Does anybody have a good suggestion on how to do this? Thank you for any hint, Merlin