If you're looking for a deal on the upcoming Call of Duty game on the 360, Call of Duty: Black Ops, Amazon has you covered. Putting the game at essentially $29.99, you can preorder the title for $49.99 and then get another $20 in credit to put towards another title after the game ships on November 9th.
We're still unclear as to the co-op modes available in the game, but given Treyarch's previous outing with World at War's zombie mode, we're willing to take that $30 gamble! Clicking the box art to go to Amazon to purchase the game also supports Co-Optimus!
Update: Looks like the sale is over at the $49.99 price, though you can still get the $20 credit.