[TECK]

If it's what Redlinemotorsports said, this is very easy.

Use this function:

PHP Code:

/**
* Checks to see if the IP address of the visiting user is allowed and defines a conditional
*
* @param    string    String of allowed IP's
*/
function check_allowed_ip($iplist = '')
{
    global $show;

    if (empty($iplist))
    {
        return;
    }

    $show['allowedip'] = false;
    $user_ipaddress = IPADDRESS . '.';
    $addresses = preg_split('#\s+#', $iplist, -1, PREG_SPLIT_NO_EMPTY);
    foreach ($addresses AS $allowed_ip)
    {
        if (strpos($allowed_ip, '*') === false AND $allowed_ip{strlen($allowed_ip) - 1} != '.')
        {
            $allowed_ip .= '.';
        }

        $allowed_ip_regex = str_replace('\*', '(.*)', preg_quote($allowed_ip, '#'));
        if (preg_match('#^' . $allowed_ip_regex . '#U', $user_ipaddress))
        {
            $show['allowedip'] = true;
        }
    }
} 


Function Usage

PHP Code:

// separate allowed IP's by a space, you could define a vB option for that
$allowediplist = '127.0.0.* 127.1.1.53';
check_allowed_ip($allowediplist); 


In your template, all you have to do is add this condition:

<if condition="$show['allowedip']">
... do your stuff for allowed users only ...
</if>

In other words, users who have an IP starting with 127.0.0.* or users with the exact IP 127.1.1.53 will be able to see your stuff.
Hope that helps.

BTW, this was not tested, it was done off my mind.