Then you've got some of the spots on the outskirts of the square. Here's a list of them:
Strand is a bookstore. An awesome bookstore. They advertise having 18 miles worth of books. New books, used books, rare books...all can be found here.
24 East 12th Street
This is a burger restaurant, but not your average burger spot. They're famous for their milkshakes. They have a toasted marshmallow milkshake that is to die for, as well as alcoholic milkshakes (let's add some vodka to that marshmallow milkshake!). Their burgers definitely aren't bad either.
841 Broadway (between 13th and 14th Streets)
Max Brenner is a genius with chocolate. His restaurant not only has good food, but also sells his chocolate. Plus a lot of his dishes use chocolate...for example, his waffle fries are dusted with chili and cocoa powder. Delicious! You can also get fondue for 2, which is really fun.