Rhino Security is an awesome little framework that provide security infrastructure for applications. I created that after having to rebuild a security infrastructure five times, due to changing requirements. It is implemented on top of NHibernate.
I would like to challenge you to implement Rhino Security in your data access strategy of choice. Here is the design, intro and implementation notes. And of course that the code itself is accessible here.
If you think that your data access strategy is awesome, show me the code. Rhino Security is a non trivial example, but it is still quite small, about 1,700 lines of code. So that is quite doable.
Oh, and I would love to see implementations on non RDBMS platforms.
I don't expect anyone to step up and do this, by the way. For the simple reason that I don't think that this is possible. And yes, that is said in the vain hope that someone will actually show me one.