Double AA batteries ($8-$40)

Xbox players are weird, and if there’s one thing they won’t give up on it’s the utility of a spare, fully-charged pack of double AA batteries. They always come in handy whether the person just hasn’t upgraded to a rechargeable battery pack yet or the pack isn’t charged and they don’t want to wait. And if you want to get really fancy with it you can get a pack of reachable AA EBLs and the charging bay ($40).