Video game purchases (systems, games, controllers, magazines, subscriptions, gadgets, etc) are only acceptable with the expressed consent of your wife, and will only be warmly received if the video game is either A) earned through hard work and sacrifice, B) is something that has extreme long term returns, or C) if it is a game your wife wants and if she will play as much or more than you.
This is a complex rule with a simple premise. If you get a new job you will probably be alright getting yourself a video game. If you work all week on a project around the house, you can probably get a new video game. If the game is Fable II then you can probably get it because your wife will enjoy it as much if not more than you do.
This rule is void if you do something stupid.