Microsoft is holding a huge Backward Compatibility Super Sale on hundreds of games for Xbox One/Xbox 360 right now. If you've been holding off on picking up Call of Duty: Black Ops 2 since it hit Xbox One in April, now would be the time. You can check the full list of discounted items on the Major Nelson Blog. Honestly, though, you don't really need the list. If you want it, it's probably on sale.
The super sale applies to 280 items (that's counting games and a few pieces of DLC) and there are currently 372 games on the official backwards compatibility list. I'm not a math professor but I'd say those are pretty good odds. And many of the items are on sale for upwards of 75 percent off.
Not sure where to start looking? Read our list of 13 backwards compatible classics for Xbox One.