RE: Hash in NYC
For hash -- the food! -- in New York City, I heartily recommend EJ's Luncheonette, sort of a yuppie diner. They have locations in Greenwich Village (6th Ave. and 10th St.), on the Upper West Side (82nd & Amsterdam), and the Upper East Side (3rd Ave. in the lower '70s). I've had both corned beef (dry, in a good way) and turkey/sweet potato (moist and yummy) and thoroughly enjoyed them. One down note: the only mustard they have is Grey Poupon, which doesn't go so well with Corned Beef, but what are you going to do?
One other note: I once saw Al Goldstein outside the one in the Village. As another passerby commented, "He's gotta eat, too."