Change for a trillion?

Because of the looming debt ceiling crisis, there's a scramble to think of alternative means of financing if Congress and the President get stuck at an impasse. One idea is that, instead of selling bonds, the Treasury could sell a trillion dollar coin to the Federal Reserve (the only entity that could possibly come up with such a vast sum, since it has the power to create as much money as it likes). It's a sign of the times that this idea is almost being taken seriously.