Only if it is a luxury sales tax, survival essentials (food, water, shelter) must be exempt.
Income tax is a horrible idea, I can't believe we have suffered it this long. Think about it. The government steals 30% right off the top, before you have a chance to spend $1 on food or shelter. Government should be at the end of the line for your money, not the front.
1) It's fair, everyone pays the same rate.
2) It's progressive, rich people buy more luxuries and more expensive luxuries, so they pay a lot more in tax. The poor pay little or no tax because they don't buy luxuries.
3) You don't have to report every detail of your life to the federal government like you do now on April 15th.
4) No exemptions for special interest groups.
5) Encourages saving instead of running out to buy latest luxury (iPod, xBox, "cool" shoes, etc.).
6) No way to get around paying taxes. Even if you pay people in cash "under the table", they still shop at Wal-Mart, so will pay taxes.
...... I can't think of any.