non touristy things to do in new york

my wife and i are on a trip in new york just for fun. we've both been to nyc a few times for sightseeing...so we arent interested in seeing esb,statue of liberty, things like that. we want to ask the locals for things like best place for sushi(she favors more quaint authentic atmosphere than hip modern sushi places) , shows that are not broadway, interesting museums, nice neighborhoods, or just anything else that migh be worth visiting. please help! were staying til tonight. thanks!