We've got a spreadsheet for our budget. It lists all the bills, due dates, amounts, and other things we must budget for. Most of the bills themselves set their budgeted amount themselves, as mortgage and other bills are generally a set amount. The rest we divide as we see fit, setting aside funds for groceries, spending cash, extra debt repayment, etc. We don't leave alot unalloted, partly because the money is tight, and partly because unalloted funds tend to get frittered away, and we don't like frittering away money. Splurges definately have their place, but we tend to try and plan them so we don't blow the budget or incur more debt.