In the case of Greece there is a geo-political card that could be played -- Russian support. Russia could easily supply Greece with oil and gas as well as refined petroleum products if needed, or arrange for them to be supplied. A similar possibility exist with Iran, especially if there is some measure of normalization with Rouhani now in office.

As to banking, during the Civil War in the USA Salmon P Chase arranged a massive loan in gold backed dollars from the big New York banks. Once the loan was granted he demanded the gold, which he withdrew. This put the civilian economy of the US onto a fiat currency basis but gave the US Government the means to finance needed imports of military goods. Foreign exchange became much more difficult for the private sector, which discouraged imports. A year later he created 2% Federal bonds, the purchase of which by banks gave the bank the right to issue bank notes up to the amount of the bond. The Congress also passed a tax on private bank notes. This created the National Banking system which, ignoring the return to the gold standard and the problems of a bi-metalic standard, essentially endured until the Fed became operational in the fall of 1914. It is true that the issue of Greenbacks directly by the Treasury during the Civil War did result in an approximately 50% loss of value compared to gold, but there were many who benefited from this inflation. There are ways a savy Central Banker can deal with FX problems, but I still maintain it would be easier were Greece to be able to help found an alternative currency union operated according to the needs of countries more like itself. Most southern peripheral countries in the Euro would qualify under that definition.

"It is not necessary to have hope in order to persevere."