Or, I should say, which does not include payroll taxes: I would like to see the payroll tax system eliminated entirely and integrated into a single income tax system.

FORBES: Flat Tax Vs. Fair Tax Vs. Herman Cain's 9-9-9 Plan

First, an income-tax system with a single rate remains progressive the rich pay a higher proportion of their income than the poor as long as it is combined with a tax-free allowance.

ECONOMIST: The Conservatives toy with a politically risky idea

The Bush Administration's proposed new savings accounts are a step--a remarkably bold one--toward a radical tax change in the U.S. This revolution is moving toward what I and others have long advocated: a flat tax--an income tax system with a single rate that would apply after a high threshold and that would exempt levies on capital gains, dividends and interest.

FORBES: Fact and Comment