Full documentation may come later, if there's enough demand.
For the moment, read this blog post: http://codeblog.jonskeet.uk/2009/09/10/generic-constraints-for-enums-and-delegates/
Then if you just want the library, install the NuGet package: http://nuget.org/List/Packages/UnconstrainedMelody
Or if you want the "Constraint Changer" to write your own generic members in the same way, build the source code from the project home page: http://code.google.com/p/unconstrained-melody/
Email me with any queries, questions, etc. (Or use the issue tracker to report bugs.) Jon Skeet, skeet@pobox.com