Using the kb_packman extension an editor can compress (archive) a complete folder in the fileadmin. This allows easy download of multiple files/folders without using an FTP client or similar software. Additionall an editor can extract archives like zip, rar, tar.gz or tar.bz2 directly on the server if the required binaries (unzip, etc.) are installed.
This allows an editor to upload a whole bunch of files at once. Altough comfortably uploading multiple files is also possible using a flash or java uploader you can also upload a complete file structure containing directories using this extension by simply extracting an archive containing the directory structure and/or files.
Of course this extension is secure against attempts to extract .php files from within an archive and against exploits by using tricky filenames. All calls to the "exec" method of PHP get properly escaped by PHP's "escapeshellarg" function.