Having lived on the other side of the river for the entire time, I can't really speak to what's in Cambridge (although I agree with those who said CBC is a good place for such a thing), but this time of year the places on Boston-side are less crowded than normal thanks to BU being out of session. Not that those are great after work type places to begin with due to the crowd they normally cater to (especially in Allston), but something to keep in mind.