From the Met to the smallest gallery in Chelsea. And even better is that you can always look for a time where you can afford to visit them all.
This wonderful time frame it is known as pay what you wish or the free museum day. Soon you will learn that you can visit the Whitney on Fridays from 7-10 pm, the MoMa on Fridays too from 4.00-8.00pm; Guggenheim on Saturdays since 6.00 pm and the Met everyday! So get prepared to organized your week around it!