The Future Perfect is my favorite place to shop for furniture / interiors, or pick up a small gift for a friend. They have a perfect mix of beautiful and strange objects, some of my favorites include the Animal Butt Magnets, Shrigley Salt & Petter Shakers, and the Bank in the form of a Pig.
You've heard about the reading room at the New York Public Library, haven't you? Then I need not go on. Just look at it. And you're allowed to hang around in there!