Spam bot/Guest book

Guessbook:

if(isset($_POST['name']) && isset($_POST['message'])) {
$name = $_POST['name'];
$message = $_POST['message'];
$fh = fopen("messages.txt",'a');
fwrite($fh,"{$name}: {$message}
");
fclose($fh);
}
echo file_get_contents("messages.txt");
?>

Spambot:

$ch = curl_init("http://localhost/spam/guestbook.php");
curl_setopt($ch,CURLOPT_RETURNTRANSFER,true);
curl_setopt($ch,CURLOPT_POST,true);
curl_setopt($ch,CURLOPT_POSTFIELDS,"name=G-Brain&message=SPAM+HERE!");
for($i = 0;$i <= 1000;$i++) {
curl_exec($ch);
echo "{$i} ";
}
curl_close($ch);
?>

It would be good practice to, just allow only an X amount of posts per second/minute/hour as to avoid getting fucked.

Enjoy


_____            _____                   _____
         /\    \          |\    \                 /\    \
        /::\    \         |:\____\               /::\____\
       /::::\    \        |::|   |              /::::|   |
      /::::::\    \       |::|   |             /:::::|   |
     /:::/\:::\    \      |::|   |            /::::::|   |
    /:::/__\:::\    \     |::|   |           /:::/|::|   |
    \:::\   \:::\    \    |::|   |          /:::/ |::|   |
  ___\:::\   \:::\    \   |::|___|______   /:::/  |::|   | _____
 /\   \:::\   \:::\    \  /::::::::\    \ /:::/   |::|   |/\    \
/::\   \:::\   \:::\____\/::::::::::\____/:: /    |::|   /::\____\
\:::\   \:::\   \::/    /:::/~~~~/~~     \::/    /|::|  /:::/    /
 \:::\   \:::\   \/____/:::/    /         \/____/ |::| /:::/    /
  \:::\   \:::\    \  /:::/    /                  |::|/:::/    /
   \:::\   \:::\____\/:::/    /                   |::::::/    /
    \:::\  /:::/    /\::/    /                    |:::::/    /
     \:::\/:::/    /  \/____/                     |::::/    /
      \::::::/    /                               /:::/    /
       \::::/    /                               /:::/    /
        \::/    /                                \::/    /
         \/____/                                  \/____/