Top 20 NuGet Unit Testing Packages

Testing Extensions
Fluent API for asserting types and properties.
NUnit Visual Studio Snippets. Almost every assert is only few keystrokes away!
PetaTest - A tiny unit testing thing for your peace of mind PetaTest is tiny but powerful, embeddable, dependency free Unit Testing framework for .NET and Mono. Supplied as a single .cs file with no additional dependencies other than what's in the GAC.
Provides a simple .NET library and the win32 / win64 Redis binaries to ease local integration tests.
Use code snippet 'assertion' to get the declaration at the top of the file. Then just use Assert.Equal(...) and the like.
Simple Data classes for testing or tutorial applications. For example, class Person with some properties and class People (a set of Person). In this release added SampleData for Silvetlight app.
StoryQ is a portable (single dll), embedded BDD framework for .NET 3.5. It runs within your existing test runner and helps produce human-friendly test output (html or text). StoryQ's fluent interface adds strong typing, intellisense and documentation to your BDD grammar.
SimpleSpeedTester is a simple, easy to use framework that helps you speed test your .Net code by taking care some of the orchestration for you. It should NOT be confused with a performance profiler such as JetBrains' dotTrace or RedGate's ANTS profiler. The SimpleSpeedTester is intende...
A testable fake SMTP server
A bootstrap package for using Selenium with NUnit and Specflow
A NUnit plugin that retries intermittently failing tests.
Build gadgeteer applications without connecting any hardware!
Fakes for interfaces and classes in the .Net Framework Class libraries.
SeleniumExtensions part of the RobustHaven.IntegrationTests
Unit test utilities from the Cellfish Toolbox.
Allows you to start IIS Express or Cassini during your test.