I wish I had that problem, my wife works so its "ours"
My wife works, too, and that's why it works so well. We use a very simple and completely fair system for this.
There are a specified and predictable amount of expenses every month for the family and house. Mortgage, utility bills, food, etc. We both pay these in equal proportion to our earnings. In other words, If I make 4 times as much as my wife, the I pay 80% of the bills and she pays 20%. Whatever is left over belongs to the person who earns it. That way we each pay an equal percentage of our income to support the household.
It happens to work out that my share equals the mortgage plus all the groceries and a good chunk of the bills. Since I have more money left over after the bills, I usually pay when we go out to eat or go someplace with an admission: I pay for the vacations to Disneyworld. I also spend my own money on mutually beneficial things that are within my interests; TV, stereo, computers, DVDs, camping trailer, GPS units, etc. I couldn't care less about stuff like drapes and wallpaper and landscaping, so if my wife wants that stuff she can buy it herself with her own money. I should also mention that I do my proportionate amount of child care, as well. The way I see it her main "job" is child care and my main job is earning money. That's the way it always "used to be", but modifying it so both people have discretionary income just makes it work more smoothly.
If my wife asks me how much a particular indulgent item I have purchased cost I tell her "It didn't cost you anything" , and I don't ask her how much she spent on a trellis and rosebushes.
I have absolutely no idea how I would be able to avoid killing my wife if I had to have every expenditure I made approved by her and vice-versa. It just seems like a guaranteed recipe for arguments and power struggles.
Randy..I knew what you were getting at with the Disneyworld thing, my comment wasn't directly aimed at you.
~daxe the offensive