In Spring 2011, the New York Public Library (NYPL) launched one of the largest culinary data projects of all time: What's on the Menu?. The NYPL maintains one of the world's largest menu collections (around 45,000 menus dating back to the 1840s). The project aims to ease searching through this massive dataset. In simplifying menu search, What's on the Menu launched the first NYPL public API.
The New York City Government has raised the bar for open government programs everywhere by launching several brand new NYC Open Data APIs, a redesigned Open Data Portal and Developer Website. The NYC Open Data Portal now has over 1,100 datasets available including 200 brand new datasets that have just been added.
The Socrata Data API or SODA is one of the foremost API resources for Government and for social data discovery. One of the major use cases for open data is of course increasing law enforcement effectiveness for analysis and transparency. One such mashup using the Socrates API is the Crime Data for San Fransisco.