array_rand

Syntax: mixed array_rand ( array $input [, int $num_req = 1 ] )
Description: Pick one or more random entries out of an array

<?php
$input = array("Neo", "Morpheus", "Trinity", "Cypher", "Tank");
$rand_keys = array_rand($input, 2);
echo $input[$rand_keys[0]] . "<br/>";
echo $input[$rand_keys[1]];
?>

OUTPUT

Neo
Trinity