SimplyTestData (nuget): It's a very subtle test data factory with flexible capabilities to customize created objects. Permanent customizations per type can be defined in order to be always applied on-the-fly to objects being created. At the same time any number of additional ad-hoc customizations can be applied in particular test case.  Generally the syntax is extremely simple. Since every customization is an Action<T> where T is the type of created object. This leads to the very clean and expressive test code.  Note that this micro-framework is NOT opposed to data generation libraries or frameworks such as NBuilder or AutoPoco but can nicely complement them in most of the cases.  For quick introduction you may want to refer to Getting Started wiki page at GitHub (follow Project Site link).
Keywords: test-data|test-factory|TDD|unit-testing|testing|custom|customization|flexible