Fish shacks like the BLT Fish Shack in New York are almost like taking a short trip to the New England shore towns, at least that's how I feel when I dine at these types of a restaurants. They are casual, they offer a large daily-fresh seafood selection, they also have a friendly bunch of people serving the food and they are more wallet friendly than some other seafood restaurants in the city.
I ate few times upstairs at the BLT Fish and I can tell you, the two only share the raw bar and the building they are in but pretty much everything else is very different from each other.
This was one of my solo missions so I walked in without a reservation and took a seat at the bar. They now serve potato chips from communal plates (I am not sure how hygienic that is...) while you wait for your meal or drink. They always have a great selection of bottled beer, beer on tap and a wine list that is a perfect match for any seafood dish.
I would normally go for the pick-your-fish or a lobster roll but because I had a late lunch I wasn't ready to eat lot so I ordered the fish tacos which was one of the daily specials and another pint of Sam Adams. I also skipped dessert but their key lime or apple pies are absolutely amazing so remember to leave some room.
Check out their web site for the weekly dinner specials which range from Surf&Turf to Clambake or All you can eat mussels to steamed crabs depending on the day but they all give you your money's worth.