In Arlington, VA, it shook the building I was in fairly well. Of course I was 12 stories up to. It lasted for about a minute. At first I thought somebody was moving a heavy object and the concrete deck was vibrating as a result. As the vibrating continued it became more intense, computer screen was shaking, windows bowing and you could hear all the HVAC duct work above the ceiling swaying back and forth. At this point I realized an earth quake was occuring. As a result, it was another marathon ride home on the subway and roadways...