Crosscheck is a JavaScript unit-testing framework capable of emulating multiple browser environments. For more information see: https://dev.thefrontside.net/crosscheck
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.