Interesting article in the Sunday New York Times:  Stealth Wealth: The Untaxed Rich, Found and Then Lost, by David Cay Johnston:

False advertising is part of the problem, and it’s right there in the name: alternative minimum tax.

What happened between 1969, when the AMT was born, and today, when it has few champions — and many people scratching their heads? And how could it be that a tax aimed squarely at rich investors who paid no income tax now hits middle-class families? …

[U]ntil another course is chosen, a law focused on rich investors who paid little or no tax is now a law that affects 23.4 million of the nation’s 90 million taxpayers. The story began on Jan. 17, 1969, three days before the Johnson administration was to end. Joseph W. Barr, who served only a few weeks as Treasury secretary, told a Congressional panel about the 155 families who paid no income tax, despite incomes of $1 million or more in today’s dollars. Mr. Barr’s report made the front page of newspapers across the country the next morning and fueled debates in coffee shops, police stations and across kitchen tables. Congress in 1969 received more letters about these untaxed Americans than it did about Vietnam, according to Michael Graetz….

[T]he stated goal of the original AMT is not being met under the successor tax enacted 21 years ago. A far greater number of well-off families still pay only small amounts of tax. More than 41,000 taxpayers with incomes of $200,000 or more in 2003, the last year for which figures are available, paid less than 10% of their income in individual income taxes. And the number of untaxed high-income families — once 155 — grew to 2,824.