Basic email detection from images

.htaccess

RewriteRule ^images/email/([a-zA-Z0-9_-]*)/images.gif$	email_detect.php?string=$1	[L,NC,QSA]

email_detect.php

<?PHP

//-- Called when a server looks at our email
//-- We'll find out who looked at our email now

//-- Woah - do some filtering on this!
$string = $_GET['string'];

//-- Who's email was this?
$user = DB::table('email_stuff')->where('string', $string)->first();

//-- Do some sanity checks here such as making sure row exists etc

//-- This is a great place to do some $_SERVER magic, such as finding the referrer etc

//-- Store hit
DB::table('email_view')->insert(array('email_address' => $email, 'time_viewed' => time()));

//-- Serve the image
//-- Here we are serving a 1 by 1 gif image
header( 'Content-type: image/gif' );
echo chr(71).chr(73).chr(70).chr(56).chr(57).chr(97).
      chr(1).chr(0).chr(1).chr(0).chr(128).chr(0).
      chr(0).chr(0).chr(0).chr(0).chr(0).chr(0).chr(0).
      chr(33).chr(249).chr(4).chr(1).chr(0).chr(0).
      chr(0).chr(0).chr(44).chr(0).chr(0).chr(0).chr(0).
      chr(1).chr(0).chr(1).chr(0).chr(0).chr(2).chr(2).
      chr(68).chr(1).chr(0).chr(59);

email_send.php

<?PHP

//-- Really simple email detection code
//-- You'll need a connection to a DB, so we can store emails -> random images

$emails = array('email@example.com', 'email2@example.com'); //etc

foreach($emails AS $email) 
{
    //-- Generate random string (Your guna want a better function here, one that checks for duplicates etc)
    $random_string = time() . "_" . "icanhaz";

    //-- Create Image URL
    $my_image_url = "http://mywebsite.com/images/" . $random_string . "/image.gif";

    //-- Store this
    DB::table('email_stuff')->insert(array('email_address' => $email, 'string' => $random_string));

    //-- Send mail, with the Create Image URL in the HTML body
    Mail::send(...)

}