Should you be the administrator of the Apache web server, what protocol(s) would you'd rather provide, for that web-developers to upload static files (html/presen/css/...), with the aim of maximum security ?
Should you be the net developer/artist, what methods would you'd rather be accessible in the Apache server, to upload static files ?

Thanks!

SCP is exactly what I'd opt for.

You may also use Filezilla for this and pretend it's unsecure FTP: http://filezilla-project.org/

SSH/SCP. It is rather simple, fast, free, and is often as secure as you would like. Options are FTP (hahahaha, yeah right) and POSTing files over HTTPS.

I give web-developers instructions on utilizing an sftp/scp client along with a login spend using scponly. This way they obtain use of upload files, however i have less concerns about the subject doing bad items to the webserver.

I personally use ssh config to limit customers to sftp on the development server then use version control to examine the alterations and move these to production with got format-patch

We deploy using Capistrano, which afaik does its work via git (over SSH) - a minimum of, within our deploy script it's.