AsyncTestFramework is a simple test framework for .NET which allows testing of asynchronous code, i.e. code which uses callbacks. In .NET, there are two main types of callback systems: those based on AsyncCallback and those based on Events. This framework supports both.
Current version, 0.2, is a proof of concept. The code can already be used for testing, but there are features which should be added, such as more Assert* methods.
I am planning to either add more functionality to this framework or attempt to integrate the functionality of this framework into NUnit. The latter is more sensible but could prove to require a significant amount of development time, which is always scarce. I'm also slightly worried that it could be difficult to persuade the NUnit team that my approach is valid, though I am of course willing to take a different approach if anyone can suggest one which requires less subversion of the .NET framework.
Jeremy Hopkin for suggestions, insight and asking me difficult questions.
The person on #c#, Freenode IRC, whose name I don't remember, for exposing the details of the .NET Event system implementation.