This is a great way to license your software made with .NET.
Open License is an Open Source project being developed by SP extreme. The Open License project goal is to develop a complete .NET License Manager. The purpose is to extend the built in License Manager framework in .NET
Open License is evolving to include many new features and improve the existing features. Currently Open License supports Constraints to limit a license (i.e. Demo, Beta, Domain, Processor, etc) and how it allows a product to be used.