You're right, it's pretty theoretical at this point. But as Chris Dixon points out, most big ideas start out looking like toys: http://cdixon.org/2010/01/03/the-next-big-thing-will-start-o...
With the financial trouble in Portugal, Spain and Greece and the imbalance in monetary and fiscal health (Contrast those 3 with Germany) within the EU, the Euro looks very shaky indeed.