XCOM: Enemy Unknown is available now from the the Xbox Marketplace's Games on Demand section. All it will cost you is a sectoid arm and a muton foot, which converts roughly to $59.99 (in the United States).

For those not stuck in underground bunkers while the planet is under attack, more cost-effective hard copy options can be delivered to your door for $10 less (or more). But how you want to go spending your hard-earned alien limbs for one of the best games of last year is your choice, Commander.