PHP generates string + numeric random number of arbitrary length

You can customize what string is generated and how long

function random($length)
{
$hash = '';
$chars = 'ABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789abcdefghijklmnopqrstuvwxyz';
$max = strlen($ chars) - 1 ;
mt_srand((double)microtime() * 1000000);
for($i = 0; $i < $length; $i++)
{
$hash .= $chars[mt_rand(0, $max)] ;
}
return $hash;
}

PHP