The Simple Web Automation Toolkit (SWAT) is a test tool that allows users to automate web application testing in multiple browsers. SWAT has a robust Editor with UI recording and SQL tools, integrates with Fitnesse, and is written in C#.
As of 5/1/2012 SWAT has been placed in a maintenance mode and is not going to receive further updates.
JsUnit is a port of JUnit to JavaScript. JUnit is a framework for building unit tests. A lot of JavaScript enabled products are supported along with command line support for automated test suites.
ajaxUnit is a way of unit-testing AJAX apps that are written in PHP & Javascript The test software can put your app in a predetermined state then compare the responseText from the XMLHttpRequest object with what you are expecting.