What to do in NYC if I`ve 5 days allready saw the tourist points and with no money wants to feel like NYer?

In these days I`ll be allready seen the tourist sites and what I`m looking for is eat the best hot dog on the streets, go to places where normally a tourist don`t have the time to go. I also want to make a tatoo too so if you have and indication of a good tatoo maker I would love it, and above all this I just want to try to feel like a real new yorker. Thanks for your help. B)