Here's an interesting factoid from Transportation Alternatives, a pedestrian and bicycling advocacy group, which recently published a report on the Top 10 Drive-to-Work Census Tracts in Manhattan:

"Government workers are far more likely to drive cars to work in Manhattan than private-sector workers... 33% of government workers drove to work in Manhattan compared to 11% of private workers. The reason: many government workers have free parking... If government workers commuted by public transportation or other means at the same rate as others, there would be 14,000 fewer cars coming into the Manhattan central business district each day."

(Hat tip: Gotham Gazette)