For local (Drupal) sites where you don't want to eat up drive space from file syncs, have apache pull them from the production sites instead. http://getlevelten.com/blog/mark-carver/dont-sync-drupal-files-local-environments-redirect-them-instead

Redirect-file-traffic

<VirtualHost 0.0.0.0:80>
  ServerName mysite.sandbox
  DocumentRoot /path/to/mysite.sandbox
  <IfModule mod_rewrite.c>
    RewriteEngine on
    # Request resides in your 'sites/default/files' folder.
    RewriteCond %{REQUEST_URI} ^/sites/default/files/(.*)$
    # File doesn't exist.
    RewriteCond %{REQUEST_FILENAME} !-f
    # Directory doesn't exist.
    RewriteCond %{REQUEST_FILENAME} !-d
    # Redirect request to your development or production server.
    RewriteRule ^/sites/default/files/(.*)$ http://dev.example.com/sites/default/files/$1 [L]
  </IfModule>    
  <Directory /path/to/mysite.sandbox>
    Options FollowSymLinks
    Order allow,deny
    Allow from all
  </Directory>
</VirtualHost>