cookies

Does anyone know how to have a cookie remember the previous page the viewer was viewing (url), so I can redirect them back there?

You could just use:
header("Location: ".$_SERVER['HTTP_REFERER'])
Then there is no need for a cookie.

EDIT:
Or if you need one, you can use:
<?php
setcookie("RefererCookie", $_SERVER['HTTP_REFERER']);
echo $_COOKIE["RefererCookie"];
?>

thanks Jmace!
I think it may help!