Input filtering...

[Slyke]

foreach ($HTTP_POST_VARS as $key=>$value) {

  $value = filter_input(INPUT_POST, $key, FILTER_SANITIZE_SPECIAL_CHARS);
  $_POST[$key] = $value;

}

foreach ($HTTP_GET_VARS as $key=>$value) {

  $value = filter_input(INPUT_GET, $key, FILTER_SANITIZE_SPECIAL_CHARS);
  $_GET[$key] = $value;

} 

Is there any reason I wouldn't want to do this on every page on my script? It protects against SQL injections, plus other mishaps (Such as XSS).