Microsoft added some backward compatibility games to the deals with gold sale. You need xbox live gold.
https://www.xbox.com/en-US/live/deals-with-gold
Spec Ops: The Line – $5,99
The Darkness II – $5,99
The Misadventures Of Pb Winterbottom – $1,99
http://marketplace.xbox.com/en-US/Product/Spec-Ops-The-Line/66acd000-77fe-1000-9115-d80254540843
http://marketplace.xbox.com/en-US/Product/The-Darkness-II/66acd000-77fe-1000-9115-d8025454088d
http://marketplace.xbo