After defeating Ares, you will enter Olympus and approach your throne as the new god of war. There are two statues at the foot of your throne; statue of Ares and the huge undead minotaur. Hack and slash at both statues until they break. After breaking them both, a message will appear. It is phone number; call it and hear what happens: 1-800-613-8840
Completing the game on God Mode unlocks an additional number (in Extras) with a unique message from the K-man himself: 1-888-447-5594
Note: Both of these numbers still work as of 2/25/2009!