In solidarity with Occupy Wall Street protesters in New York City similar movements have cropped up in both Los Angeles and Chicago. They say they are inspired by revolutions in the Middle East, but protests over economic grievances in Spain and elsewhere in Europe are a closer comparison as anti-corporate demonstrations spread across the United States.   As the Occupy Wall Street protest entered its third week Monday, it is being taken more seriously this week as the New York protest expects to swell with support from trade unions. The demonstrators are protesting what they believe is greed and corruption among banking and business leaders. -Photos by agencies