Bush says national sales tax worth considering

Wrong, wrong, wrong. If anything, sales taxes need to be eliminated, not the other way around. Unlike the income tax, the sales tax is a regressive tax, meaning it disproportionately affects lower and middle income earners. Also, sales taxes are a pain in the ass for small businesses to deal with since different counties and municipalities within a state often have different rates.

On a related note, for those conservatives and libertarians who still believe the flat tax is a good idea, you need to go back and actually read Adam Smith's Wealth of Nations which endorsed a system of progressive taxation:

"The subjects of every state ought to contribute toward the support of the government, as nearly as possible, in proportion to their respective abilities; that is, in proportion to the revenue which they respectively enjoy under the protection of the state ....[As Henry Home (Lord Kames) has written, a goal of taxation should be to] 'remedy inequality of riches as much as possible, by relieving the poor and burdening the rich." -Adam Smith.