Most proposed balanced budget amendments attempt to limit spending in some fashion. I propose instead a system where government can spend without restriction, but tax rates adjust to fully fund it the following year. For example, if this year the government spends 20% more than it collected in taxes, next year's taxes automatically increase by 20%. If the government runs a surplus, taxes then decrease proportionately the following year.
This accomplishes several things:
1. It ensures all spending is always paid for within a year.
2. It ends political fighting over debt ceilings and tax rates.
3. It acts as a check against military adventurism. The Iraq War would have never had the support it did if it required an automatic tax increase to pay for it.