Quixote is an open source library for unit testing CSS. It lets you make assertions about your pages' elements, their relationships, and how they are actually styled by the browser. It has a compact, powerful API and produces beautiful failure messages.
factory_girl is a fixtures replacement with a straightforward definition syntax, support for multiple build strategies (saved instances, unsaved instances, attribute hashes, and stubbed objects), and support for multiple factories for the same class (user, admin_user, and so on), including factory inheritance.
phpspec is a development tool, designed to help you achieve clean and working PHP code by using a technique derived from test-first development called (spec) behaviour driven development (BDD), or SpecBDD.
Catch stands for C++ Automated Test Cases in Headers and is a multi-paradigm automated test framework for C++ and Objective-C (and, maybe, C). It is implemented entirely in a set of header files, but is packaged up as a single header for extra convenience.
tSQLt is a database unit testing framework for Microsoft SQL Server. tSQLt is compatible with SQL Server 2005 (service pack 2 required) and above on all editions. tSQLt allows you to implement unit tests in T-SQL. This is important as you do not have to switch between various tools to create your code and your unit tests. tSQLt also provides the following features to make it easier to create and manage unit tests.