This deal has ended.
Update: the deal is dead! This is no longer available. Today only, Amazon has
Two 1600-Point XBox 360 Live Cards (add a quantity of two to your cart) for only $29.28 ($10 price drop will occur at last stage of checkout). That's the best price online by a long shot for this many points. Shipping is free and there's no sales tax (except K, KY, ND, NY, WA).