How Congress shapes your commute

Even our daily sojourns to the office are affected by the twists and turns in the U.S. tax code. If you drive to work, your employer can cover up to $230 per month in parking costs tax-free. And in recent years, if you take mass transit, your employer has also been able to reimburse you, tax-free, for up to $230. This latter program was part of the 2009 stimulus bill, and one Businessweek survey found that, when companies do offer it, many workers really do shift to public transportation.

http://www.washingtonpost.com/blogs/ezra-klein/post/how-congress-shapes-your-commute/2011/10/19/gIQA7GHOxL_blog.html