<?php

$seed = str_split('abcdefghijklmnopqrstuvwxyz'
                     .'ABCDEFGHIJKLMNOPQRSTUVWXYZ'
                     .'0123456789!@#$%^&*()'); // and any other characters
    shuffle($seed); // probably optional since array_is randomized; this may be redundant
    $rand = '';
    foreach (array_rand($seed, 5) as $k) $rand .= $seed[$k];
    
    echo $rand;