If you plan on blitzing the major sights, consider buying one of the numerous multi-attraction passes (see www.nycgo.com/attraction-passes). Getting one of these discount cards will save you a wad of cash. Go online for more details, and to purchase these passes.
New York CityPASS (www.citypass.com) Buys you admission to six major attractions (including the Empire State Building) for $122, saving around 40% if purchased separately.
The New York Pass (www.newyorkpass.com) This pass gives you one-day access to some 90 different sites for $119. Multiday passes also available (from two to 10 days).
Downtown Culture Pass (www.downtownculturepass.org) Purchase this $25 three-day pass for free admission (and shop discounts) at a handful of sites in Lower Manhattan, including the Museum of American Finance and the Museum of Jewish Heritage, both locations where you can purchase the pass in person.
Explorer Pass (www.smartdestinations.com) A pass that lets you choose between three and 10 attractions for discounted admission. You pick the sites from among 63 options, including the MoMA, the Intrepid Museum, Sightseeing cruises and the Top of the Rock. Prices start at $84 for three sites, up to $199 for 10 sites.