It really is amazing, we've been living off one salary our entire married life, and my sweetheart hasn't held a job since we moved to the states. It's amazing what happens once you start budgeting. I've always budgeted my entire life and I just cannot understand how people can just spend money without thinking. I budget so I CAN spend money and not have to think about it because I have a budget for it.
The rule we've gone by is we both have our allowance, and bigger purchases we talk about, plan for, save up, research, then see if we even still want it.