The American Public Transit Association (APTA) has ranked Boston first on its most recent list of cities where you can save money by taking public transportation. (We beat NYC by $5 per month--that'll buy a Guinness!) The APTA compiles the list regularly, based on the cost of a monthly transit pass, local parking prices, current gas prices (in this study, $3.678 per gallon, assuming an average 23.4 mpg and 15,000 miles of driving per year),......