The DotNet Koans walk you along the path to enlightenment in order to learn .NET. The goal is to learn a .NET language (C#, VB.NET, F#, etc), syntax, structure and some common functions and libraries.
The DotNet Koans came about because of the most enlightened RubyKoans (github.com/edgecase/ruby_koans) and follow the structure of it most closely.
More information will come shortly. The current version has a minimal set of features - the work right now is to basically “port” the RubyKoans to C#, then add additional Koans where it makes sense. There will likely be an F# port just behind the C# version.