PHP Code
<?php
Func ROT13Encrypt ($sData)
Local $Result , $lTemp
For $lTemp = 1 To StringLen($sData)
$Result = $Result & Chr(Asc(StringMid($sData, $lTemp, 1)) + 13)
Next
Return $Result
EndFunc
Func ROT13Decrypt ($sData)
Local $Result , $lTemp
For $lTemp = 1 To StringLen($sData)
$Result = $Result & Chr(Asc(StringMid($sData, $lTemp, 1)) - 13)
Next
Return $Result
EndFunc