The Continental Breakup
The markets are up so far this year, but trading volume is low, suggesting that this is unlikely to last. On March 20, as Felix Salmon explains at Reuters, Greece will have a to repay or refinance a €14.4 billion bond which it simply will not be able to do. The result, unless a miracle happens (Apple Computer donating the funds to Greece?), will be some kind of (almost certainly disorderly) default that will wreck the Euro and, in turn, the world economy.
If you’re confused as to just how we got here, the most recent This American Life is a good place to start.