The Frank Stella's are the best. They are all over the city and they always look amazing. Two of my favorites are the Saatchi and Saatchi lobby (pictured) and the Citi Corp building in Midtown.
Founded and designed by Japanese-American artist Isamu Noguchi (1904–1988), The Isamu Noguchi Foundation and Garden Museum preserves the working atmosphere of the artist's former studio in New York.
I read that the design of Central Park's curving spaces was a Romantic counter to the geometry of Enlightenment-era gardens. I heard this design was influenced by landscape painting, where its foreground, middleground, and background constantly shift as you walk the paths. I find new pockets and features every time I'm there. One of my favorite spots is with the Central Park Dance Skaters, a group that roller skates in circles all day to vintage electro funk. These characters generously lend you the feeling of being in your own 1980's New York film.
The different views of the skyline are unbelievable. I especially like rooftop views from different apartment buildings. Try to get on top of an apartment building. This is the view from my apartment...