the most easy and effectiev way to know Where in boston can you cash your work paycheck fast when banks are closed is to use internet facility
By sitting in your home you can easily find the answer of this question that which which sites are informing you about the paycheck cash when banks are closed and which site is fullfiling your requirements
Or you can use facility of internet which will tell all thier offers in your required branch area
So contact to internet as soon as possible my friend.
But its totally depends upon your wish either you want to do this job by siiting at home or by physically going there but i thnk internet is best option.