I've got a WordPress blog (self-located) and that i want the customers from a link like my-wordpress.com/see?pass=0cc175b9c0f1b6a831c399e269772661 to determine private posts as though these were registered. Is the fact that possible? How do you make that happen? Thanks

This is not an effective way to do things, but when you want to deal with it such as this, you'd must validate the "pass" data against whatever passwords is around the "private website." Something similar to...

<?php
$myPass = '0cc175b9c0f1b6a831c399e269772661';
if ($_GET['pass'] == $myPass) {
   // Correct!
} else {
   // Wrong
}
?>

Edit: Ideally you'd have a bit of software that validates the code at entry and produces a wordpress session for that user. That might be more complicated though.