Eating out in Cambridge is very easy: there is a whole plethora of budget dining restaurants. Many restaurants have special lunch menus, with smaller size portions, some also offer all-you-can-eat buffets. Remember, if you’re too lazy to go out, or if the weather isn’t too good, GrubHub and Foodler are always there for you! (you can order food online to be delivered, often with no additional charges, and with frequent promotions). Nice bets with online food orders in the area are e.g. Passage to India and Wok’N’Roll restaurants (both from Porter Square).
Below, only the very few budget restaurants I frequently returned to:
Japanese food court is a well hidden gem, since you have to know where to look to find it. Near Porter Square, you enter the Lesley University building just by the City Sports store, to find 3 excellent Japanese soup restaurants, including the legendary Sapporo Ramen, a sushi place, all very affordable and tasty. There is also a more fancy Japanese restaurant there.
Kebab Factory is the place to go to for cheap Indian lunch (all-you-can-eat buffet for around 10$, according to our Indian friends it is better than Tamarind Bay).
LE’s Restaurant located in the Square is known for good quality, affordable Vietnamese food.
A great place to go for fast, but quite good (and extremely cheap, below 10$!) Mexican food is Anna’s Taqueria. They have a couple of locations in Cambridge, and the one closest to Harvard is on Porter Square (there is also one at MIT).
Ana’s Taqueria may well be the best Mexican fast food in general Boston area.
Last, but not least, if you want something practically on campus and practically next to Berkman-Klein, but not Caspersen (be it for the prices or for the taste), you can check out Lesley’s cafeteria (you just enter downstairs, into Lesley’s building) with “all you can eat” buffet in lunch hours. It usually has lots of veggies and healthy food choices.