The solution to the Euro crisis" is IMO neither an exit of any member from the Eurozone or any "haircut"! The solution is Economic & Political (i full) union of the EU or the Eurozone!
In the last few years what we have actually seen the failure of the global financial system, not of the Euro!
Only a fully united EU or Eurozone can lead to Democracy over Financial Agorocracy result.
Europe must lead in this "revolution"!