JsUnit is a unit testing framework for client-side JavaScript in the tradition of the XUnit frameworks. Development began in 2001. As of 11/28/2009, development has moved to GitHub: http://github.com/pivotal/jsunit
BugEye is an XML-based unit test creation framework. Being XML-based, it can be easily translated to almost any language. The current translations are C#, Java, JavaScript, and Visual Basic. Future translations include C++, Python, Perl, and PHP.
Testpilot is a browser based unit testing framework for testing websites. With it you can record the keystrokes and mouse events for a session and play them back automatically. You can include assertions for values in inputs DIVs or JavaScript variables.
jsAssertUnit is a unit testing framework based on assertions, helping JavaScript developers to test their code. Failing assertions about the program state are tracked in a Reporter window of a DOM compliant browser : IE5+, Mozilla, Netscape 6+, etc.