WASHINGTON: Millions of middle-class Americans could end up paying more to Uncle Sam in the next 10 years, thanks to an obscure provision of the tax code known as the Alternative Minimum Tax. Families of four with incomes of $58,300 in 1996 tax dollars will be hardest hit. Ironically, the AMT was designed to close loopholes for the very rich. What can you do about it? Money Daily reports that lawmakers decided not to tackle the worsening situation because the media and taxpayer groups have not been vocal about it. So you may want to stop browsing the Web for a minute to e-mail your congressperson.