As the mainstream .NET world is finally finding it’s way to Object Relational Mapping, the Alt.NET guys are already looking at the next logical step: document databases.
Howard van Rooijen wrote a very good introduction to help you take your first steps to a NoSQL world:
http://howard.vanrooijen.co.uk/blog/2010/04/04/a-dotnet-developer-guide-to-mongodb-and-norm/
As always don’t forget; “The right tool for the right job…”