Porter Square Books, in Cambridge, Mass. They've got a reasonable selection of books for browsing, and a really nice tea and coffee counter. And it's handy to the T (subway) stop, so I can get off the train, get a cup of tea, look at books, and then take the bus the rest of the way to my girlfriend's place. One small nice thing is that they have a "buy n, get one free" deal for coffee and tea, like a lot of places (I think n is a dozen) but don't make me keep a card. I just give them my name, and they update the record. (Places where I have to get the card stamped, I mostly don't, because I forget to have the card with me, or it's buried in the bottom of my bag.)