$20 off Halo 4 ($39.99)

Retailer: Gamestop

Platforms: Xbox 360

Link: http://bit.ly/lr0Nqi 

Well, it looks like 343 Industries has done it. They've sold more copies of Halo 4 than Bungie ever did with a previous title. Whether you're looking to spend your time hopping around maps like a lunatic, enjoying some of the Spartan Ops content, or just bum around testing things out, you're free to do so in Halo 4. Throw the $20 towards some of the impending DLC or use it to pay for your tragically necessary Xbox Live subscription that's lapsing soon.