The Metropolitan Museum of Art has a “pay what you want” policy. You can pay a dollar or you can pay 25, or more, whatever you want. Check out Central Park. If the weather is nice, you can just hang out and people watch. Same with Washington Square Park. Any park, of course, but Washington Square Park is world renowned for eclectic people and street performers. Walk on the High Line. I haven’t been, but it’s very popular now. If you’re into shopping, or want NYC souvenirs, go to Chinatown. Just north of Chinatown is the Village and Soho. Funky, famouse and fun.