There are billions of dollars that could be recouped from the "underground economy" under FairTax. Also, you need a valid Social Security number to qualify for the prebate. Think that might take care of some of the illegal immigration problem?
A good friend of mine recently became the primary FairTax contact for his congressional district, and he's fired up! It will be a difficult road, because Congress has the tax code as a tool to engineer social behavior. With recent economic events, maybe things are "up for grabs" enough where we have a window of opportunity to get something done. Sign me up.