This native Brooklynite has a sampled more than a few slices of the best NYC and Westchester has to offer:
Denino's in Port Richmond
Di Fara's in Midwood
Grimaldi's in the Heights
Joe & Pat's on the Island
John's on Bleeker
Johnny's in Mount Vernon (Westchester)
Lento's in Bay Ridge (now closed)
Lombardi's on Spring
Patsy's in East Harlem
Pizza Wagon in the Ridge
Sal's in Mamaroneck (Westchester)
Sofia's in Harrison (Westchester)
Spumoni Gardens (or L&B) in Gravesend
Totonno's in Coney Island
All offer (or once did) great pizza, but a few are (were) truly exceptional.
Totonno's back in the 60's and 70's was truly an experience, especially since it was empty most of time due to the fact that people other than those who worked or lived in the immediate area were afraid to venture a block beyond Nathan's due to the crime, and this was in broad daylight. I attended high school a half-mile away and and an extended lunch break with a few friends at either Nathan's or Totonno's was always a blast.
John's rocked in the 70's, but I've always been more partial to the thin crust of the hot sausage, mushroom and fresh garlic pies with a thin sheen of oil once served at Lento's.
Pizza Wagon served an outstanding Sicilian with an always fresh square featuring a thin, chewy crust during the 70's and 80's.
Today, Sal's serves an exceptional slice, but for pies I'm with Johnny's of Mount Vernon all the way.