For a nice, inexpensive haircut that may come with the type of criticism that your mother would dish out, go to 22 Pell Street Hair salon in Chinatown. My friend Dani took me to this place and I like it because they give good haircuts for less than $30.
My main man is Nelson, a hairdresser from Hong Kong who does not hold back when it comes to hair advice. Don't be offended if he tells you your hair is "SO oirrrllly, SO greeesy", he will suggest an excellent shampoo and cut your hair so that it looks voluminous and neat. If he tells you to get the shampoo, buy the shampoo because he really knows his stuff. His remarks are truly for your benefit because he really does want the best for your tresses.
After you get your hair cut, go to Shanghai Cafe on 100 Mott street in Chinatown. I went here last night and I was very happy. We ordered the pan-fried shanghai noodle which was like crispy cantonese noodles, the beef and onion dish, the cold tofu and vegetable appetizer, and cong you bing (scallion pancake). You MUST order the pork xiaolongbao (soup dumplings). For four people, the bill came to a very student-friendly $50.
Sunrise Mart is a Japanese supermarket by St. Marks street. They stock all sorts of things like miso soup packets, sushi ingredients, bento boxes, Japanese cosmetics and magazines. It is a tiny place that you wouldn't find randomly because you have to go upstairs to get there. Definitely worth checking out if you like to cook Japanese food. I like it better than M2M, the overpriced Asian supermarket down the street.
Saigon Market on University Place between 11th and 12th is a charming and surprisingly spacious restaurant. All I have to say is that their grilled porkchop is to die for. Check out their lunch special. I feel like this would be a great place to go with a large group because they have big tables.