Actually here's one I found. You could book a Grand Tower Room with two Queen Beds for 578 or two rooms.
MGM Grand "No Regrets offer *Additional discount on top of our already low online rates *Offer is non-refundable and may not be canceled or changed. Jan 23 - Apr 30, 2008 (Expires 4/30/08)
Las Vegas Hotel Promo Codes Promo Code: INB150