Duke Nukem Forever, Amazon just might have a deal for you. The online retailer is currently offering a $10 video game credit with all pre-orders of the Duke's latest outing (which was recently delayed again, incidentally). The credit applies to all available platforms.
If you plan on snagging a copy for the Xbox 360, you might also look into a new one-year Xbox Live Gold subscription, which Amazon is offering for $40, a savings of $20 over the usual price. After all, you can't play the new butt-slapping multiplayer without Xbox Live, now can you?