Open Source Testing Automation Tools
Watir - 'Web Application Testing in Ruby', a free open-source family of web automation libraries in Ruby. The libraries support IE on Windows, Firefox on Windows, Mac and Linux, Safari on Mac, Chrome on Windows and Flash testing with Firefox. Note: Firewatir (targeting Firefox) is now merged with Watir. For a listing of additional tools that are available to extend some capabilities - see the Watir site and also Alternative Tools for Web Testing' page at the OpenQA site for more info.