The New York State Archives, like the state itself, is a large, sprawling, diverse landscape, with many wonders to behold. But it's easy to get lost.
Archives' Digital Collections, which are arranged by Topics:
A few favorites here are:
You genealogical types can search for family members and other individual people in a large, somewhat peculiar assortment known as the Universal Name Indexes. This is one-stop searching on a number of databases:
There is separate name searching at the Motion Picture Division Film Script Index 1927-1965 and at the huge New York State Civil War database, where a search on the last name Smith turns up almost 7,000 results.
There are some Archive Exhibits online:
America's Civil War
I also suggest you stop off at Excelsior, the main catalog of the New York State Library/Archives/Museum. Note that there are several search options here, including one for Archives, a separate one for Digital Collections, and yet another for the Historical Documents Inventory. I think you can get all online materials at once by clicking Search Entire Catalog, then Power Search, and then use the Location pull-down to select Online.