Spark API SDK is an open-source, lesser GPL-licensed .NET library that supports access to the financial market data API from Spark (http://iguana2.com/spark-sdk).
The SDK comprises an open-source C# code base with detailed examples and code comments on how to interface with the Spark API and process the data streams. This is encapsulated in SparkAPI project which a component containing all the classes and helper functions required to easily utilise the API. A set of sample applications demonstrating some simple uses of the API are also available.
The component also supports replay from historical files and does not require a connection to the Spark servers when working in file replay mode. This makes it ideal for those wishing to learn how to manipulate and utilise institutional-grade market data in non-institutional setting.
Spark is a market data provider that supplies real-time exchange grade data feeds for Australian and New Zealand equity and options markets.
Wow, this SDK was exactly what I was looking for. It's uncanny. Admittedly I wrote it. But it's still fantastic.