Jon and I have the "frivolous expense budget" for exactly this reason. We essentially give ourselves each a monthly budget on paper, and make deductions as we buy stuff or put cash in our wallets that gets spent on non-essential items. This way, if he buys more games and Legos that I think we don't need, I don't complain. Likewise, I don't feel guilty for doing things like going horseback riding with friends if it comes out of my budget. We have very different spending habits, but this keeps the emotions surrounding money under control.

--Beth