The current Xbox Live deal of the week is centered around Arcade titles -- some good, some great, and definitely worth considering with the discounts in place. Before we go any further, it's worth noting that an XBL Gold membership is required to partake, because of course it is.
There's also Gotham City Imposters (600 MSP), Warhammer 40,000: Kill Team (320 MSP), Hell Yeah! Wrath of the Dead Rabbit (480 MSP), Bionic Commando Rearmed 2 (480 MSP), and Black Knight Sword (400 MSP). Shame about the aforementioned restriction, but at least these prices are more reasonable than they have been in prior years.