i agree, and i often think things out explicitly that way. i actually take a step further though. some fraction of my expenses are fixed (rent, insurance, food to an extent) which leaves me with some percentage of disposable income, call it 25% for this example. so if i get paid $20/hr, a $20 item that isn't absolutely necessary doesn't cost me one hour of work, but rather four, because three quarters of that money is "already spent". suddenly it doesn't seem like i need the shiny new gadget that badly.