Much better than the flat tax, is the Fair Tax. Not only would we see a massive influx of jobs to our country, we would have greater purchasing power. The basic necessaties wouldn't be taxed nor would our savings.
For those that don't understand what the Fair Tax is, I recommend you go to FairTax.org and do a little research. A good book to read about the Fair Tax is "Fair Tax: The Truth" by Neal Boortz and Congressman John Linder. Mike Huckabee is also a strong supporter of the Fair Tax