The answer depends largely on where you work, but for downtown Boston, Sail Loft is the spot. It's close to the financial district and North End and is the best place to go for drinks after work. Fantastic view, great crowd and good drinks!
I used to work in Harvard Square and JH's was the perfect spot for after-work drinks. Great, cheap food and good beer with tons of Harvard grad students and young professionals. Great tables for bigger groups.
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