My name is Aivar Maasik, and I am holding master degree from Tallinn University of Technology with the major in Business Finance. I have been studied in details the history of the world currency exchange systems, and I am supporter of such a great idea to create a new world single currency.
The definition of a world or global currency refers to a hypothetical single global currency, and I propose the "DEY" (acronym for Dollar Euro Yen). Currently we are working on design of acronym first letter "D" with two horisontal lines, similar to " €".
There are many different variations of the idea, including a possibility that it would be administered by a global central bank or that it would be on the gold standard.
At my personal opinion the new SGC exchange system should be administered by global central bank and the exchange rate system must be based on old and best ever "gold standard". For example 100 DEY = 1 Ounce of gold. During that time the world economy had a most stable growth without any significant economic shocks. More than that the new currency will lead to inflation free or controlled inflation economical environment, decrease the protectionism and increase the world markets efficiency, it will bring up the real competition on a more fair game conditions. From the opposite it will increase risk that MNEs (multination enterprise) will begin to choose them home country based on countries fiscal policy in order to optimize their profit (it relates to income taxation system difference). However the idea is worth it.