Any file type upload

function wpse_6533_map_unrestricted_upload_filter($caps, $cap) {
  if ($cap == 'unfiltered_upload') {
    $caps = array();
    $caps[] = $cap;
  }

  return $caps;
}

add_filter('map_meta_cap', 'wpse_6533_map_unrestricted_upload_filter', 0, 2);