These Pythom bindings for Bittrex can interface the Bittrex API with an existing python program. The library is open source, however, the Bittrex API requires an API key for use. The library is not officially owned by Bittrex, though it's usage is endorsed by Bittrex on their API documentation page.
DMG has launched an API platform to help combat money laundering and fraud in Bitcoin transactions. The Bitscore Risk API provides a Bitscore that offers a measure of "tainted" currency that flows through transactions on a given network. The Bitscore helps quantify risk on a network.
FantasyData.com, NFL statistical data provider, offers the FantasyData NFL API. The API gives developers access to NFL data (e.g. team stats, live scores, season information, box scores, and more). The API targets web and mobile app owners who develop apps for the fantasy football market. Many of the most popular fantasy football apps have already integrated with FantasyData's APIs.