It is time for the U.S. government to require the inclusion of sales tax in the listed shelf price of all items sold within the United States. Currently, the latent visibility of sales taxes is being used by businesses as a psychological tool to to garner favorable opinions to pricing. It is time for $19.99 to turn $20.
Including taxes in the listed item price would prompt business to do one of two things: They would either raise or lower their price marginally to a close whole number. This would make purchases more streamlined which could potentially encourage more sales thus providing a slight boost to the economy.
Another potential good this reform might help enable is coinage system refinement. If prices are listed in increments of five cents, the wasteful penny could be eliminated.