This page shows how dynamically can PHP work.

Suppose you want check online your sensible links, but you don't want to show them publicly,
. . . then you can just type in the input field of this form the following variable : My Private Links

...$var value will appear here
[  ]
This script can also work out for redirecting purposes, just by setting the appropriated code into a conditianal sentence. The code of this script is layoutted in this page subframe
You can do the same for GET-variables and use this system as a sort of password to get avilable all your sensible informations that you might need if using a public computer, in that case do not forget to place appropriate headers to disable chronology storing of the page containing this script :
header("Pragma: no-cache");
header("Cache-Control: no-store,no-cache,must-revalidate,post-check=0,pre-check=0",false);
Code   Home

<? $var=$HTTP_POST_VARS['var']; echo"<div align=center><br><br><br> <table border=0><tr><td align=right vAlign=top> <form action='$PHP_SELF'method=post> <input type=text name='var' size=12> <input type=submit value='Set a post variable'><br> <font style='font-size:14px;font-family:arial;color:green'> <i>...\$var <b>value</b> will appear here <big><b>&rarr;</b></big></i></font><br> </td><td vAlign=bottom>"; if($var=="My Private Links"){ $links="<a href=>My ISP</a><br> <a href=ss.php>Server Settings</a>"; $var=$links; } else{$links="";} echo"<font style='font-size:14px;font-family:arial;color:green'> <big>[</big>&#160;$var&#160;<big>]</big></font></td></tr></table>"; ?>