In the past, when evaluating tax proposals, neither the Congressional Budget Office nor the Joint Committee on Taxation were permitted to factor in the effect of economic growth on tax revenue.

FORBES: Congress Embraces Dynamic Scoring. Somewhere, Mitt Romney Shakes His Fist In Anger

Because the HAA harnesses the vast pool of money that is today distributed inefficiently through the tax break for employer-provided care, and then couples it with clever cost-control mechanisms, the Congressional Budget Office and the Joint Committee on Taxation have judged that the HAA will be revenue neutral or even revenue-enhancing within a few years.

ECONOMIST: Health care

On the other side of the Hill Wednesday, Congressional Budget Office Director Peter Orszag told a House committee that simply giving companies emissions allowances could result in "windfall" profits for firms that rely heavily on fossil fuels.

FORBES: Getting Warmer