Making a server download/upload

[MrApples]

A friend of mine has a terrible upload connection speed, due to living in Scotland, and as updating his site requires transmitting rather large files, I'd like to write a script that can download files, and upload files for him.

But how would I go about doing so? And if the site does not support a "upload from URL", can it still be done? I do know PHP, I just need the specific commands.

[MoT3rror]

You can use the file (http://us3.php.net/file) function but your friend is still going to need to upload it somewhere.