New York City is having its second app challenge, known as BigApps.  According to the BigApps website:

The NYC.gov Data Mine can be found at http://nyc.gov/data. You are required to use at least one data set from the Data Mine in your application. NYCEDC and DoITT coordinated with over 40 City agencies and commissions to provide the datasets, with 15 new city agencies, including the Department of Environmental Protection, School Construction Authority and Campaign Finance Board, participating in DataMine for the first time. CompStat and City budget data, taxi and limousine trip data, complaints to the Department of Buildings, and real-time traffic information.

The best apps in the challenge will win $20,000.  Last year’s winners were Big Apple Ed, Taxihack, WayFinder NYC, and NYC Way.