As the markets imply a virtual certainty that Greece will default, possibly triggering a new round of contagion and banking crises, Jeff Kleintop, on thestreet.com, says it might not be that big a deal:

If Greece defaults, and there are a number of reasons why that may not happen, the impact may be more akin to Argentina than Lehman Brothers. In December 2001, the government of Argentina initiated the largest government debt default on record, suspending interest payments and principal repayments on bond issues with a face value of more than $81 billion. Many large global financial institutions that held Argentinean debt were still undercapitalized following the 2001 recession and took substantial losses, yet a global financial crisis did not take place and the global recovery continued.

Here is the famous Der Spiegel article on Germany preparing for the possibility that Greece could leave the Euro zone.