I'm certain you already know by now but the markets took a serious hammering today. While some are claiming a trade error took us down nearly 1000 points on the Dow before recovering the proximal causes of this recent selloff are still with us:
Greece is on a slow downward spiral towards default or a very severe recession / depression. After the most recent bailout announcement the markets calmed down for one day before continuing to de-risk. The contagion has spread and now Spain, Portugal and Italy are possibly next. Who and when is next I don't know.
China continues tightening and is determined to stamp out rising property prices. I have some more information that I intended to post on this but I've been a bit busy. Fortunately I was finishing up de-risking a few portfolios yesterday.
The Fed's purchase of mortgage backed securities ended March 31 so from now on the money supply will start to contract. The Fed is effectively tightening right now.
The home buyer tax credit deadline ended a few days ago so the housing bounce is over with.
Bank lending continues to contract for both households and small companies.
I've gone over these items before but the Greek situation started the ball rolling downhill. Until several of the above items are resolved what happened today was not a 'one time event'.