In the run-up to the August 2011 controversy about the raising of the debt ceiling, which requires congressional approval and was initially opposed by Republicans (who control the House of Representatives) who demanded more spending cuts, Yale Law Professor Jack Balkin proposed a novel solution. He claimed that there was a loophole in the law that would allow the Treasury to issue two $1 trillion platinum 'commemorative' coins which would then be deposited with Federal Reserve who would then deposit funds with the Treasury in return, thereby bypassing the legal requirement of Congress to control raising the debt ceiling.
With another executive fight with congressional Republicans looming over the debt ceiling in March, the 'trillion dollar coin' proposal has gained traction among some commentators, the most prominent being the left-wing Nobel Prize winning economist and New York Times columnist Paul Krugman:
Be Ready To Mint That Coin - NYTimes.com
The idea and Krugman's endorsement has been subject to ridicule from commentators on both sides of the political divide, but Krugman took particular offense to a comedy skit on Jon Stewart's 'The Daily Show' that mocked his endorsement of the 'trillion dollar coin':
Krugman, Stewart in trillion-dollar coin tiff - POLITICO.com (includes video).