Hudson is a popular web-based continuous integration server, written in Java. Hudson is used in 17.000+ server installations worldwide in small, medium and large companies alike, including eBay, Hewlett-Packard, MySQL, JBoss, Xerox, Yahoo, LinkedIn, or Goldman-Sachs. It allows you to automate your software build chain, e.g. monitoring changes in version control systems, triggering new builds, testing artifacts, sending notifications, deploying to production servers, and much more. Hudson is liked for its ease of use and broad extensibility via 250+ plugins.

http://www.methodsandtools.com/tools/tools.php?hudson