This deal has ended.
Buy.com has a promotion for a $45 eCoupon (valid for future Buy.com orders) when you buy one of several Xbox 360 bundles through 6/25. The bundles start at $530 and the net $485 (effectively) is a pretty good deal. Overstock had an Xbox 360 platinum for $352 recently but that did not include the extra wireless controller or the game(s) that the bundles do. Shipping is not free, however (it is around $17); there is no sales tax (except CA, MA, MD, TN).