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.
Currently there are no documentation about the framework and if you want to use it in a higher level, it's a bit complicated to learn by your self. However SWAT is very usefull and intuitive and we don't need to install many programs like other functional frameworks. strongly advise
Excellent GUI automation for web based development.