First, locate the Porter Exchange, a Japanophile's haven adjacent to the Porter Square T-Stop. It has a grocery store and several tiny specialized eateries (noodles, sushi).
Bluefin (Cambridge): In the Porter Exchange. Decent-quality and affordable sushi. I like the sashimi bento.
Toraya (Arlington): Near Blue Ribbon BBQ up Mass Ave. This unassuming sushi joint is my favorite, especially the thoughtfully-prepared and very tasty sashimi bento that's only available during lunch. Arrive before noon on weekends to avoid crowds.
BBQ: Blue Ribbon (Arlington) vs Redbones (Somerville)
There's an age-old rivalry between Blue Ribbon BBQ and Redbones. I prefer Redbones, esp. either the massive "holy cow, I just ate a barnyard" all-you-can-eat lunch combo (which you'll find if you go out of your way to ask them for the lunch menu which oddly isn't default at lunchtime), or the St. Louis / Memphis rib combo.
We like the ever-crowded Dali (Somerville) for tapas, though the pricing makes it best for parties of >4.
Atasca (Cambridge) serves up our favorites: pork w/clams, salt cod, shrimp w/tomatoes and goat cheese, and tripe. (That's four dishes, although I'd be willing to have it mixed together.)
Avoid: Summer Shack (Cambridge @ Alewife)
J-Fav and I think it's funny that an overpriced, mediocre seafood place like the Summer Shack could have won so many honors for value and family quality. Augh! Stay away! (Not "hah, hah" funny, but "Mulder, could you look at this?" funny, as J-Fav would say.)
Look for the Improper Bostonian, a free glossy hipper-than-thou magazine that appears weekly those - uh - free magazine cubby streetside things. It is full of new restaurants, museum exhibit openings, and concert listings. Unfortunately, it's also full of itself.
Sandwiches and Fresh Bread
We love the sandwiches at High-Rise Bakery, which has several locations (Cambridge x 2, Boston). Unfortunately, it has earned the nickname "High-Price," as J-Fav calls it, and is usually swarming with a weekend crowd of people looking very... entitled. Gosh darn it, though, it has great food.
Pancakes / Diners
You've already met our favorite, the Deluxe Town Diner (Watertown). I enjoy the short stack of chocolate chip pancakes and then go into a coma.
HamburgersHands-down, I love just about any burger at Mr. & Mrs. Bartley's Burgers in Harvard Square. (No restrooms, though!)
You never know when you'll need just the right edition of a particular Gertrude Stein piece. Or not. In any case: the Grolier Poetry Book Shop (Cambridge, in Harvard Square).
Hundreds - I mean hundreds - of games of all sorts from around the world: The Games People Play (Cambridge, btwn. Harvard Sq. and Central Sq.)