If you have more than a little free time, there's an abundance of museums, bookstores, restaurants, and nifty things in and around Harvard Square to occupy you. Everything on this list is in easy walking distance, and we've marked them on a map (~2MB PDF) if you'd like to check them out:
If you prefer art to arthropods, one admission fee admits you to both the Arthur M. Sackler Museum and the Busch-Reisinger Museum. (The Fogg will be closed for renovations.) Finally, the Collection of Historical Scientific Instruments at Harvard is free to the public (but only on weekday afternoons!), and curated by a friend of ours from Scottish dancing.
If you need something to listen to while you read your new books, Newbury Comics in the Garage offers new and used CDs, with Godzilla toys, anime accessories, and a coin-operated fortune teller thrown in for spice. (Yes, we thought it was a comic shop too.) Looney Tunes and Planet Records are more traditional used CD stores.
The reception will be catered by Cafe of India, a very tasty Indian restaurant. Tamarind Bay is also excellent, offering less traditional regional cuisine. It's too small for large groups, but a great choice for a small, elegant meal. Tanjore is a more typical Indian restaurant, and also very good. Located just above Tanjore, Smile Thai Cafe offers Thai food, as you may surmise, as does 9 Tastes. Wagamama is a twist on a traditional Japanese noodle bar. And Lê's in the Garage offers sit-down Vietnamese food with incredibly fast service. Their Pho (noodle soup) is tasty, cheap, and very nearly big enough for a quick dip.
While we're in the Garage, there are a few other quick meals to be found there: chowder, pizza, and reasonably tasty burgers. But for pizza the place to go is Pinocchio's, and you can find top-quality burgers at Mr. Bartley's and B.Good.
The famous Cardullo's makes excellent and ginormous deli sandwiches (grab a table outside to eat them), made by people who know their luncheon meats, and it's worth browsing even if you're not hungry — because you will be soon enough. Their tottering shelves are stocked with fine chocolates, imported preserves, fancy honeys, and $175 bottles of balsamic vinegar. Z Square, just off the square, offers quick paninis and crêpes in the café upstairs, and fine dining below.
Traditional New England fare can be found at Henrietta's Table in the Charles River hotel. Legal Sea Foods is right next door, and Dolphin Seafood is on the other side of the Square. Both offer fresh-caught fish.
Sandrine's Bistro, for the deep-pocketed diner, offers Alsatian and French cooking, and the most interesting doorway in Harvard Square.
If you're a godless heathen hippie, or just a vegan, you might enjoy Veggie Planet, which turns into Club Passim in the evenings. The word "rennetless", whatever that means, features prominently in reviews. Ten minutes' walk down Mass Ave. is the Greater Boston Buddhist Cultural Center, which offers vegetarian dining in their tea house. As one reviewer put it, the food is "clean, wholesome, and made with Zen love man." Fire+Ice is a grill-your own place, where you can choose meat or non-meat goodies as you wish.
Late July in Boston — perhaps some ice cream will be needed? Lizzy's homemade ice cream is right down the street from the church. Herrell's is another nearby option. If you need to satisfy a chocolate craving, Burdick's is a few minutes away on Brattle; they sell chocolate penguins that are both whimsical and delightful. Finally, Finale offers elegant dessert creations and other café treats.